Rise of Macedon The rise of Macedon , from a small kingdom at the periphery of Classical Greek affairs to one which came to dominate the entire Hellenic world ( and beyond ) , occurred in the space of just 25 years , between 359 and 336 BC . This ascendancy is largely attributable to the personality and policies of Philip II . Sources . Intact and relatively detailed histories of Greece cover the period ca . 500 – 362 BC , in the form of Herodotus ' s " The Histories " , Thucydides ' s " History of the Peloponnesian War " , and Xenophon ' s " Hellenica " . However , no extant history specifically covers the relevant period of Greek history ( 359 - 336 BC ) . The main source for the period is Diodorus Siculus ' s " Bibliotheca historica " , written in the 1st century BC , which is therefore very much a secondary source . Diodorus devotes Book XVI to the period of Philip ' s reign , but the action is much compressed , and due to the scope of the work , this book also contains details of happenings during the same period elsewhere in the ancient world . Diodorus is often derided by modern historians for his style and inaccuracies , but he preserves many details of the ancient period found nowhere else . Diodorus worked primarily by epitomizing the works of other historians , omitting many details where they did not suit his purpose , which was to illustrate moral lessons from history ; his account of the period therefore contains many gaps . Another surviving work for the period is Justin ' s epitome of Pompeius Trogus ' s " Philippic History " . Justin ' s epitomised history is also much condensed from the original , and covers not only Philip ' s reign , but also the history of Macedon before him , and the exploits of Philip ' s son , Alexander the Great . Justin is generally very negative towards Philip . These surviving histories are complemented by fragments of other histories , including Theopompus ' s 58 - volume history of Philip ( which was the source for much of Trogus ' s Philippic history ) and by contemporary epigraphic sources . Outside the brief notices of Philip ' s exploits which occur in Diodorus and Justin , further details of his campaigns ( and indeed the period in general ) can be found in the orations of Athenian statesmen , primarily Demosthenes and Aeschines , which have survived intact . Since these speeches were never intended to be historical material , they must be treated with great circumspection , particularly given the identity of the authors . Demosthenes and Aeschines have been described as " a couple of liars , neither of whom can be trusted to have told the truth in any matter in which it was remotely in his interest to lie " . For instance , the Peace of Philocrates ( made in 346 BC ) is known primarily from their speeches ( both called " On the False Embassy " ) , made in 343 BC , when Demosthenes prosecuted Aeschines for his involvement in making the peace treaty . In his speech , Aeschines poses as the champion of the peace treaty , when he had in fact opposed making peace ; conversely , Demosthenes , who had been a proponent of peace in 346 BC represents himself as part of the " war - party " . The arguments made in the speeches therefore refer to the political situation in 343 BC and not the situation when the treaty was made , which makes teasing out the actual historical threads rather difficult . Background . Greece in the early 4th century BC . In the aftermath of the Peloponnesian War , the militaristic city - state of Sparta had been able to impose a hegemony over the heartland of Classical Greece ( the Peloponessus and mainland Greece south of Thessaly ) , the states of this area having been severely weakened by the war . This state of affairs was resented by many of the Greek city states , which had traditionally been ferociously independent , and led directly to the Corinthian War of 395 – 387 BC . Sparta emerged from this conflict with its hegemony intact , though only as a result of Persian intervention , which led to the so - called King ' s Peace . The fragility of Spartan dominance had been demonstrated however , and in the next decade , the Thebans would revolt against Sparta . The Spartans were unable to successfully quell the revolt , leading to " de facto " Theban independence . Then , after several years of desultory conflict , the Thebans finally met the Spartans in open battle at Leuctra ( 371 BC ) , and under the leadership of Epaminondas inflicted an unprecedented defeat on the Spartan army , killing the Spartan king Cleombrotus in the process . Following up on this victory , Epaminondas invaded Peloponnesus in 370 BC , and began dismantling the basis of Spartan dominance . Spartan power rested on the forced labour of the helots of Messenia , which allowed the entire male Spartan population to dedicate themselves to warfare . This focused military training system had previously enabled Sparta to exert power out of all proportion with its small population . However , after their losses at Leuctra , the Spartans were unable to resist the Epaminondas ' s invasion , and he marched into Messenia and liberated the helots , thereby permanently crippling Sparta . The Thebans then began to extend their influence over Greece , effectively replacing the Spartan hegemony with their own . The Theban generals Pelopidas and Epaminondas campaigned all over Greece for the next 9 years to further Theban power and influence . In 362 BC , Epaminondas ' s fourth invasion of the Peloponnesus , which reached its climax at the Battle of Mantinea , brought almost every state in Greece into the conflict , on one side or the other . Although the Thebans and their allies were victorious at Mantinea , Epaminondas was killed , and Theban losses were heavy . Xenophon , summing up his account of Mantinea , suggests that : The years of conflict which resulted from the Theban attempts to reorganise Greece had left much of the country war - weary and exhausted ; a general peace ( excluding only a recalcitrant Sparta ) was therefore concluded between all the states of Greece in the aftermath of Mantinea . With the death of Epaminondas and significant loss of manpower at Mantinea , the Thebans returned to their more traditional defensive policy , and within a few years , Athens had replaced them at the pinnacle of the Greek political system , and Theban influence faded quickly in the rest of Greece . It was the Athenians , and their second confederacy , who would be Macedons ' s main rivals for control of the lands of the north Aegean , and a major theme during the period was the regular state of war between Macedon and Athens . Philip ' s accession . In 360 BC , the Macedonian army under Perdiccas III had been defeated in battle by the Dardania n tribe of Illyria ; Perdiccas and 4 , 000 troops had been killed . The Illyrians began to prepare to invade Macedon ; meanwhile , the Paionia ns were ravaging Macedonian territory , the Thracians were preparing to invade in support of the pretender Pausanias , as were the Athenians , in support of a different pretender , Argeus . In short , Macedon was in another of its periodic crises . The nominal heir of Perdiccas , his son Amyntas IV , was only an infant . Philip , the sole surviving son of Amyntas III , was the obvious candidate to rule Macedon and was acclaimed by the army , probably as king . It is also possible that he was initially acclaimed as regent for Amyntas III , and later usurped the throne , although if so , he did not harm Amyntas . Either way , Philip became king by 359 BC , and began energetically attempting to save Macedon from destruction . The Macedonian recovery ( 359 – 358 BC ) . Reconstruction of the army . Philip ' s first priorities were to reconstruct the Macedonian army , and restore the morale of both the army and the people . He held a series of assemblies with the Macedonian people , and " exhorting them with eloquent speeches to be men , he built up their morale " . He exhaustively re - trained his men with new tactics and equipment . In particular , he instigated the use of the phalanx formation by the Macedonian foot - soldiery , and equipped the troops with 6 metre long pikes ( the " sarissa " ) , in contrast to the 2 - 3 metre spear ( " doru " ) used by Greek hoplite s . Diplomacy . At the same time Philip engaged in a flurry of diplomatic activity . He bribed Berisades , son of the Thracian king Cotys , to withdraw Thracian support for Pausanias , and thereby prevented the Thracian invasion . Similarly , he bought off the Paionians with gifts in exchange for their withdrawal from Macedon . Philip may also have concluded a treaty with the victorious Dardanian king Bardylis , possibly surrendering large parts of Macedon in exchange for peace . Although no evidence remains of such a treaty , the fact that Illyrians did not follow up their victory despite Macedon ' s weakness is suggestive that some agreement was reached . Philip also married Bardylis ' s daughter ( or niece ) , which may have formed part of the treaty . At any rate , Philip ' s diplomacy gave Macedon some breathing space and time for recovery . Battle of Methone . Philip realised that the sole intention of the Athenian support for Argeus was to recover Amphipolis ( see below ) , which they hoped to do by placing Argeus on the throne . Philip therefore withdrew the Macedonian garrison from Amphipolis and declared it autonomous , to undermine the purpose of Athenian support for Argeus . The Athenian expedition , led by Mantias , still landed at Methone on the Macedonian coast , with 3 , 000 mercenary troops . Mantias now declined to leave Methone , so Argeus instead led the troops to the ancient Macedonian capital of Aegae , hoping that the populace would declare him king . However , the people of Aegae showed no interest in doing so , and Argeus therefore marched back to Methone . On the way , he was attacked and defeated in battle by Philip , many of the Athenian mercenaries being slain and the rest taken captive . According to Diodorus , this victory did much to restore the morale of the Macedonian army , and gave the soldiers encouragement for the battles to come . Having defeated the last immediate threat to Macedon , Philip returned to diplomacy . He released the Athenian prisoners immediately , and sent ambassadors to Athens . He was prepared to abandon all claim to Amphipolis , and this , coupled with his treatment of the Athenian prisoners , persuaded the Athenians to make peace with him . Paionia and Illyria . The following year ( 358 BC ) , Philip heard that the Paionian king , Agis , had died . He took this opportunity to march his army in Paionia , where he defeated the Paionians , and compelled the tribe to acknowledge allegiance to Macedon . Philip was now able to turn to the Illyrians , who were still occupying much of upper Macedon ( whether agreed by treaty or not ) . He held an assembly of the army , gathered together a force of 10 , 000 men and 600 cavalry and marched into Illyria . Bardylis , hearing of the preparations , sent ambassadors to Philip , proposing peace on the basis of the status quo . Philip rejected this , insisting that the Illyrians must withdraw completely of Macedonia , so Bardylis instead prepared for battle , raising 10 , 000 men and 500 cavalry , according to Diodorus . Diodorus preserves the only account of the battle , which Beloch suggested may have taken place near Monastir . He says that : According to Diodorus , some 7 , 000 Illyrians died in the battle . The Illyrians withdrew from Macedon , and sued for peace . After this campaign Philip had established his authority inland as far as Lake Ohrid and gained the favour of the Epirotes , who has also been at war with the Illyrians . Thessaly . Justin and Diodorus both say that Philip also invaded Thessaly in 358 BC , In the years up to 370 BC , Thessaly had enjoyed a brief ascendancy in the Greek world , after being unified under Jason of Pherae , who was appointed " Tagus " ( chief magistrate ) of Thessaly . However , Jason was assassinated in 370 BC , and his son Alexander became Tagus . Alexander ruled harshly , and other states of the Thessalian League therefore withdrew their support for him , resulting in a desultory conflict in which both Macedon ( under Alexander II ) and eventually Thebes became embroiled . This conflict eventually ended in 364 BC when the Thebans were victorious over Alexander , and imposed a peace settlement on Thessaly . However , with the weakening of Thebes in the aftermath of Mantinea , on - off conflict within Thessaly continued . Alexander was himself assassinated in 358 BC , by his wife ' s brothers Lycophron and Tisiphonus , who became tyrants in his place . According to Diodorus , the Aleuadae , the noble family which dominated politics in the northern Thessalian city of Larissa were opposed to these new tyrants , and requested Philip to aid them . Although Diodorus says that Philip defeated the new tyrants , Buckler considers it more likely that that Philip ' s appearance on the scene allowed the Aleuadae to negotiate a peace settlement with Pherae from a position of greater strength . Philip seems to have come away from the expedition with new wives from both Larissa ( Philinna ) " and " Pherae ( Nicesipolis , Jason ' s niece ) , which is suggestive of a negotiated settlement ; certainly , as Buckler says , " Philip came away from Thessaly with a foot in both camps " . Philip appears to have a had a strong interest in Thessaly from the start of his reign , even despite his problems elsewhere . There are several probable reasons for this interest . Firstly , and most pressingly , Philip probably wanted to take control of the border region of Perrhaebia ( traditionally part of Thessaly ) , in order to secure Macedon ' s southern border . Secondly , since Larissa controlled the main north - south routes between Macedon and Thessaly , friendly relations with the Aleuadae would help protect Macedon " and " give Philip access to the rest of Greece . Thirdly , Thessaly had plentiful resources that Philip could see the long - term potential of exploiting : Summary to 358 BC . Through his frenetic activity since coming to the throne , Philip had successfully shored up the Macedonian situation , defeating or making peace with Macedon ' s erstwhile enemies , whilst securing most of Macedon ' s borders , and revitalising and retraining his army . Conquest in the North ( 357 – 353 BC ) . Amphipolis ( 357 BC ) . Philip ' s next aim was to secure Macedon ' s eastern flank , which bordered Thrace , and in particular the city of Amphipolis . Amphipolis was a major strategic point , situated on the Strymon River , where it controlled the only crossing point on the lower reaches of the river , and therefore access to and from Thrace . Eastwards expansion of his kingdom therefore required that Philip control Amphipolis . The Athenians had founded a colony there in the previous century , only to lose control of it during the Peloponnesian War . The Athenians were very keen to recover Amphipolis , partly because of its history , although the Amphipolitans were not inclined to return to Athenian control . However , the main reasons were because of the location of Amphopolis close to forests needed for shipbuilding , and because it controlled the gold and silver mines of Mount Pangaion . The importance of Amphipolis to the Athenians during this period cannot be overstated ; " their longing for it was constant and extreme " . Philip began besieging Amphipolis is 357 BC ; the Amphipolitans , abandoning their anti - Athenian policy , promptly appealed to Athens , offering to return to its control . However , during the siege , Philip sent a letter to Athens saying that he would hand over the city once he captured it ( thus appearing to follow the same policy as he had in 359 BC ) . The Athenians , thus lulled , waited to see whether he would . The Athenians may also have been unable to send help to Amphipolis . During the summer months , strong northerly winds blow into the Aegean Sea ( the Etesian winds ) , making it difficult for the Athenians to send ships north . Philip was to make repeated use of the Etesian winds , campaigning during those months ( or in winter ) , when the Athenian navy would be unable to send assistance to his enemies . The Athenians seem to have offered Philip Pydna in exchange for Amphipolis , perhaps during the later stages of the siege , but it is not clear whether Philip agreed to this . By this stage the Social War of 357 – 355 had broken out between Athens and their erstwhile allies , and they would now have been unable to intervene to help Amphipolis . Philip eventually succeeded in breaching the walls of Amphipolis , through the use of siege engines and battering rams ; his forces then stormed and captured the city . Philip expelled those who were ill - disposed to him but , according to Diodorus , treated the rest of the population considerately . Pydna and Potidea ( 357 – 356 BC ) . During the siege of Amphipolis , the Chalkidian League , led by Olynthus , began to fear Philip ' s territorial ambitions ( since Amphipolis also controlled access to Chalkidiki ) , and therefore sought to ally with Athens against him . However , the Athenians still hoped to receive Amphipolis from Philip and so refused . Philip himself feared an alliance of the powerful Chalkidian League and Athens , so he moved to reassure the Olynthians by offering them an alliance on very advantageous terms . As part of the agreement with Olynthus , Philip was to capture the city of Potidea , located in the territory of the Chalkidian league . Potidea was at that time under the control of Athens , and represented a threat to the stability of the league . Philip had no intention of handing over Amphipolis to the Athenians , but acted as if he was just delaying the transfer of the city . He seems to have gone straight on to besiege Pydna after capturing Amphipolis . The Athenians , perhaps still hoping to receive Amphipolis if they allowed Philip to take Pydna , do not seem to have tried to intervene ( and may not have been able to ) . Pydna seems to have fallen to Philip by treachery , in either 357 or 356 BC . In 356 BC , Philip then besieged and captured Potidea , thus marking the beginning of true hostilities with Athens . As promised , he handed Potidea over to the Olynthians , and let the Athenian garrison depart freely back to Athens , since he did not want to cause undue offense to the Athenians ( " he was particularly solicitous toward the people of Athens on account of the importance and repute of their city " ) . The Athenians were by this time fully engaged in fighting the Social War , and were unable to respond effectively to Philip ' s moves against Potidea and Pydna . Alliance against Philip ( 356 – 352 BC ) . In 356 BC , in response to King Philip ' s machinations , the Athenians allied with the kings of Illyria , Paionia and Thrace , to try to block his advance . Thrace was by now ruled by three kings , descendents of Cotys ; in the west was Ketriporis , the son of Berisades ( Cotys ' s second son ) ; in the centre , Amadokos II ( Cotys ' s third son ) , and in the east Kersebleptes ( Cotys ' s first son ) . Whether Athens allied to all three Thracian kings is a matter of conjecture ; certainly at least Ketriporis joined the alliance . If Kersebleptes did ally with Athens , he appears to have relatively quickly cast off this allegiance , in favour of extending his realm as the expense of Amadokos and Ketriporis . According to Diodorus , Philip marched on his enemies in this alliance before they had chance to combine , and forced them to ally to Macedon instead . However , other sources suggest that the picture was actually much more complex , and that Philip in turn defeated each of the powers over the next few years , with the exception of Athens . According to Plutarch , an army under Parmenio defeated the Illyrian king Grabos in 356 BC , shortly after the conclusion of the siege of Potidea . Grabos then became a subject ally of Macedon . The following year , Philip seems to have defeated Ketriporis , and reduced him to the status of a subject ally , although information for this campaign is very limited . He is also presumed to have defeated the Paionians at some point during this period , although there is no explicit record of this . There is no evidence that any of these allies received any substantial aid from Athens , which was still too preoccupied with the Social War . Krinides ( 356 BC ) . In 356 BC , whilst Parmenion campaigned against the Illyrians , Philip campaigned in Thrace , and captured the town of Krinides , which had been founded by Thasos in 360 BC . He changed the name to Philippi , after himself , and greatly increased the population . He also greatly improved the gold mines in the surrounding area , the effects of which are described by Diodorus : The capture of Krinides was thus , in the long term , a very significant event in Philip ' s rise to power . Maroneia and Abdera ( ca . 355 BC ) . Polyaenus recounts that Philip attacked and reduced Abdera and Maroneia ( both cities on the coast of Thrace ) during a single campaign , but does not say when . Diodorus does not mention this campaign , making its position within the overall chronology difficult to place . Buckler suggests that following . According to the Athenian politician Demosthenes , Kersebleptes met Philip at Maroneia ( in Thrace ) , together with the Theban general Pammenes , and came to an agreement with Philip ; furthermore , he states that Amadokos was hostile to Philip at the time . Demosthenes says that the Athenian general Chares filed the report about the meeting between Philip , Pammenes and Kersebleptes ; and Polyaenus says that after Philip ' s Maroneia campaign , Chares ambushed Philip ' s fleet off the coast of Neapolis . Since it is recorded that Neapolis appealed to Athens for aid against Philip in 355 BC , it is a strong possibility that these events all took place in 355 BC . It is not entirely clear what occasioned this meeting between Philip and Kersebleptes ; Buckler suggests that Philip and Kersebleptes agreed to divide Thrace between them , leaving Kersebleptes free to attack the other Thracian kings ( to try and reunite the Thracian kingdom ) , and leaving Philip free to campaign elsewhere . Conversely , Cawkwell and Sealey suggest the Maroneia campaign was in 353 BC ( though without explicit justification ) . The Maroneia campaign might therefore have been part of the campaign that Philip fought against Cetriporis ( probably 355 BC ) , or a camapaign against Amadokos ( probably 353 BC ) ; Siege of Methone ( ca . 354 BC ) . The chronology for activities in Greece during the years 355 – 352 BC is not entirely clear ( see below ) . Philip certainly started besieging Methone , the last Athenian possession in Macedon , during this period , but different historians choose different dates for this siege . There are two main theories , either 355 – 354 BC , as favoured by , for instance , Buckler , or 354 – 353 BC , as favoured by Cawkwell . At any rate , Philip began the siege , but was by his standards frustrated in his attempt to take it , and the siege dragged on for nearly a year . During this time there were two failed Athenian attempts to relieve the city . Philip was to lose an eye during the siege when he was hit by an arrow . Despite the injury inflicted on him by the defenders , he eventually agreed terms with the citizens of Methone , allowing them all to depart with one garment each . Buckler suggests that this lenient settlement may have been the result of the Thessalian request to intervene in the Sacred War ( see below ) ; anxious not to miss this opportunity , Philip sought to end the siege as quickly as possible . Summary to ca . 354 BC . By 354 / 353 BC , in just 5 years since his accession , Philip had unified Macedon and turned it into the dominant power in Northern Greece . He had completely reduced Athenian influence in the region , and was allied to the other major Greek power in the region , the Chalkidian League . He had , in the process , secured access to the Aegean sea , which had been an age - old problem in Macedon , since suitable sites had been monopolised by Greek colonists in the Archaic period . Furthermore , he had overhauled and re - trained the army , which was now battle - hardened , and he now had a supply of ready money to pay for more troops . This rapid rise in the power of Macedon was in part due to Philip ' s exceptional military and diplomatic skills . However , it was also in part due to the weakened state of the major powers of Greece . Sparta had never recovered from Epaminondas ' s liberation of Messenia , whilst in turn Thebes was still weakened by Epaminondas ' s death and the aftermath of Mantinea . Athens , as discussed above , was embroiled in a war with its allies ; in 355 BC , the Athenians agreed a peace that left many of its former allies independent , severely weakening Athenian power . Although these powers protested against Philip ' s actions , they had too many other problems to attempt any intervention ; Philip thus went largely unchallenged until 354 BC . Thessaly and the Sacred War ( 356 – 352 BC ) . Background . The Third Sacred War ( often just called ' the ' Sacred War ) broke out in 356 BC , and would present Philip with his first real opportunity to expand his influence into the affairs of central and southern Greece . The war was ostensibly caused by the refusal of the Phocian Confederation to pay a fine imposed on them in 357 BC by the Amphictyonic League , a pan - Greek religious organisation which governed the most sacred site in Ancient Greece , the Temple of Apollo at Delphi . Behind the religious element , there probably lay a display of " realpolitik " in bringing charges against the Phocians , instigated by the Thebans . At this time , Thebes controlled a majority of the votes in the council , and at the autumn meeting in 357 BC , the Thebans were able to have both the Phocians ( for the cultivation of the sacred land ) and the Spartans ( for occupying Thebes some 25 years previously ) denounced and fined . Since the fines for both parties were " unjustifiably harsh " , the Thebans probably expected neither party to pay , and thus to be able to declare a " sacred war " on either . In response , the Phocians , under the leadership of Philomelos , seized Delphi ( which was situated within the boundaries of Phocis ) , and asserted the ancient claim of Phocis to the presidency of the Amphictyonic League , intending to annul the judgment against themselves . There seems to have been some sympathy in Greece for the Phocians , since other states could see that " the Thebans . . . had used the Amphictyony to pursue petty and destructive vendettas " . The Phocians were supported by Athens ( perennial enemies of Thebes ) and unsurprisingly Sparta , who hoped to see their own fine wiped out when the Phocians seized Delphi . However , Philomelos plundered the treasury of Apollo to pay for mercenaries , thus raising a powerful army , but drastically altering the opinion of the other Greek states . In winter 356 / 355 BC , a " sacred war " was declared against the Phocians by the Amphictyonic council , with the Thebans being the major protagonists . The war started relatively well for the Phocians , but a severe defeat was inflicted on the Phocians at Neon by the Thebans in either 355 or 354 BC , and Philomelos was killed . Undeterred , Onomarchos took over the Phocian effort , and raised new mercenaries to carry on the fight . Chronology of the Sacred War . The ancient sources for the sacred war are scant , and generally lacking in firm chronological information . Modern historians ' dates for the war have therefore been hotly debated , with no clear consensus . It is generally accepted that the war lasted 10 years , and ended in summer 346 BC ( one of the only firm dates ) , which yields a date of 356 BC for the beginning of the war , with Philomelos ' s seizure of Delphi . After Philomelos ' s defeat at Neon , the Thebans thought it safe to send the general Pammenes to Asia with 5000 hoplites ; as has been discussed , Pammenes probably met with Philip at Maroneia in 355 BC , presumably on his outward journey . Buckler , the only historian to produce a systematic study of the sacred war , therefore places Neon in 355 BC , and suggests after the meeting with Pammenes , Philip went to begin the siege of Methone . Other historians have placed Neon in 354 BC , because Diodorus says that the battle took place while Philip besieged Methone which Diodorus ( at one point ) places in 354 BC . However , Diodorus ' s chronology for the sacred war is very confused — he dates the start and end of the war a year too late , variously says the war lasted 9 , 10 or 11 years , and included the siege of Methone twice under different dates — and his dates cannot therefore be relied upon . Disregarding the dates , most historians agree upon the same sequence of events for this part of the Sacred War . The principal question is therefore when that sequence started . Thus , Buckler ( as well as Beloch and Cloche ) dates Neon to 355 BC , Methone to 355 – 354 BC , Philip ' s first Thessalian campaign to 354 BC , and his second to 353 BC . Conversely , Cawkwell , Sealey , Hammond and others lower all these dates by one year , beginning with Neon in 354 BC . First campaign in Thessaly . The Sacred War appears to have laid way for renewed conflict within Thessaly . The Thessalian Confederation were in general staunch supporters of the Amphictyonic League , and had an ancient hatred of the Phocians . Conversely , Pherae had allied itself with the Phocians . In either 354 or 353 BC the Aleuadae appealed to Philip to help them defeat Pherae . Philip responded positively , perhaps unsurprisingly : Philip thus brought an army into Thessaly , probably with the intention of attacking Pherae . Under the terms of their alliance , Lycophron of Pherae requested aid from the Phocians , and Onormarchos dispatched his brother , Phallyos with 7 , 000 men ; however , Philip repulsed this force before it could join up with the Pheraeans . Onomarchos then abandoned the siege he was currently prosecuting , and brought his whole force into Thessaly to attack Philip . It is possible that Onomarchos hoped to conquer Thessaly in the process , which would both leave the Thebans isolated ( Locris and Doris having already fallen to the Phocians ) , and give the Phocians a majority in the Amphictyonic council , thus enabling them to have the war declared over . Onomarchos probably brought with him 20 , 000 infantry , 500 cavalry , and a large number of catapults , and outnumbered Philip ' s army . The exact details of the campaign that followed are unclear , but Onomarchos seems to have inflicted two defeats on Philip , with many Macedonians killed in the process . Polyaenus suggests that the first of Onomarchos ' s victories was aided by the use of the catapults to throw stones into the Macedonian phalanx , as they climbed a slope to attack the Phocians . After these defeats , Philip retreated to Macedon for the winter . He is said to have commented that he " did not run away but , like a ram , I pulled back to butt again harder " . Second campaign in Thessaly . Philip returned to Thessaly the next summer ( either 353 or 352 BC , depending on the chronology followed ) , having gathered a new army in Macedon . Philip formally requested that the Thessalians join him in the war against the Phocians ; the Thessalians , even if underwhelmed by Philip ' s performance the previous year , realistically had little choice if they wanted to avoid being conquered by Onomarchos ' s army . Philip now mustered all the Thessalian opponents of Pherae that he could , and according to Diodorus , his final army numbered 20 , 000 infantry and 3 , 000 cavalry . Pagasae . At some point during his campaigns in Thessaly , Philip captured the strategic port of Pagasae , which was in effect the port of Pherae . It is unclear whether this was during the first or second campaign ; both Buckler and Cawkwell suggest that it took place in the second campaign , before the Battle of Crocus Field . By taking Pagasae , it is possible that Philip prevented Pherae from being reinforced by sea during his second campaign . Buckler suggests that Philip had learnt his lesson from the previous campaign , and internded to cut Pherae off from outside help before attacking it . Battle of Crocus Field . Meanwhile , Onomarchus returned to Thessaly to try and preserved the Phocian ascendancy there , with approximately the same force as during the previous year . Furthermore , the Athenians dispatched Chares to help their Phocian allies , seeing the opportunity to strike a decisive blow against Philip . Subsequent events are unclear , but a battle was fought between the Macedonians and the Phocians , probably as Philip tried to prevent the Phocians uniting forces with the Pheraeans , and crucially , before the Athenians had arrived . According to Diodorus , the two armies met on a large plain near the sea ( the ' crocus field ' ) , probably in the vicinity of Pagasae . Philip sent his men into battle wearing crown of laurel , the symbol of the Apollo ; " as if he was the avenger . . . of sacrilege , and he proceeded to battle under the leadership , as it were , of the god " . Some of the Phocian mercenaries supposedly threw down their arms , panged by their guilty consciences . In the ensuing battle , the bloodiest recorded in ancient Greek history , Philip won a decisive victory against the Phocians . In total , 6 , 000 Phocian troops had been killed including Onormarchos , and another 3000 taken prisoner . Onomarchos was either hanged or crucified and the other prisoners drowned , as ritual demanded for temple - robbers . These punishments were designed to deny the defeated an honourable burial ; Philip thus continued to present himself as the pious avenger of the sacrilege committed by the Phocians . Buckler states that : " Nor should one automatically assume that a mass - drowning . . . would shock the Greek world . Even the mild - tempered Isocrates felt that the Phocian mercenaries were better off dead that alive . . . Dreadful indeed was the punishment , but it was entirely consistent with Philip ' s role as Apollo ' s champion " . Re - organisation of Thessaly . It was probably in the aftermath of his victory ( if not before ) that the Thessalians appointed Philip " Archon " of Thessaly . This was an appointment for life , and gave Philip control over all the revenues of the Thessalian Confederation , and furthermore made Philip leader of the united Thesslian army . Philip was now able to settle Thessaly at his leisure . He first probably finished the siege of Pagasae , to deny the Athenians a landing place in Thessaly . Pagasae was not part of the Thessalian Confederation , and Philip therefore took it as his own , and garrisoned it . The fall of Pagasae now left Pherae totally isolated . Lycophron , rather than suffer the fate of Onomarchos , struck a bargain with Philip , and in return for handing Pherae over to Philip , he was allowed , along with 2000 of his mercenaries , to go to Phocis . Philip now worked to unite the traditionally fractious cities of Thessaly under his rule . He took direct control of several cities in western Thessaly , exiling the dissidents , and in one case refounding the city with a Macedonian population ; he tightened his control of Perrhaebia , and invaded Magnesia , also taking it as his own and garrisoning it ; " when finished , he was lord of Thessaly . " Thermopylae . Once satisfied with his reorganisation of Thessaly , Philp marched south to the pass of Thermopylae , the gateway to central Greece . He probably intended to follow up his victory over the Phocians by invading Phocis itself , a prospect which greatly alarmed the Athenians , since once he had passed Thermopylae , he could also march on Athens . The Athenians therefore dispatched a force to Thermopylae and occupied the pass ; there is some debate as to whether other contingents may have joined the Athenians at Thermopylae . The Athenians were certainly there , since the Athenian orator Demosthenes celebrated the defence of the pass in one of his speeches . Cawkwell suggests that the Athenian force was the one that Diodorus says was dispatched under Nausicles consisting of 5 , 000 infantry and 400 cavalry , and that they were joined by the remnants of the Phocians and the Pheraean mercenaries . However , Buckler argues that Diodorus never mentions Thermopylae , and the force under Nausicles was sent to help the Phocians the following year ; instead , he believes that another Athenian force held the pass unassisted . Although it might have proved possible to force the pass , Philip did not attempt to do so , preferring not to risk a defeat after his great successes in Thessaly . Summary to 352 BC . Cawkwell describes 352 BC as Philip ' s " annus mirabilis " . His appointment to high command in Thessaly was a dramatic increase in his power , effectively giving him a whole new army . His actions as the " avenger " and " saviour " of Apollo were calculated to win him goodwill amongst the Greeks in general . As a result of Philip ' s increased power and influence , Worthington suggests that by the time of Demosthenes ' s " First Philippic " ( 351 BC ) , Philip was already unstoppable in his aim to control Greece . Strategic situation . The stalemate at Thermopylae pointed the future direction of the ongoing conflict between Philip and the Athenians . Athens was a significant naval power , whilst Macedon had no real navy to speak of . Conversely , Macedon had a very powerful army , especially with the addition of the Thessalians after 352 BC , which Athens could not hope to match . The Athenians could therefore prevent Philip attacking Athens by sea , but not by land — unless they could occupy Thermopylae in time . The pass was narrow enough to make troop numbers irrelevant , and could only be bypassed with some difficulty , meaning the Athenians could hope to resist Philip there ; Thermopylae therefore became the key position in the conflict . The Athenians also began to realise that they could not hope to reclaim Amphipolis , or defeat Philip , and must instead act on the defensive ; as Demosthenes said : " the war at the outset was concerned with taking revenge on Philip , now at its conclusion with not suffering at Philip ' s hands " . From Philip ' s point of view , once he controlled Amphipolis , he could operate in the North Aegean unimpeded , especially if he campaigned during the Etesian winds , or in winter , when the Athenian navy could do little to stop him . However , he could not easily advance into Greece , to attack Athens for instance , if Thermopylae was held against him . Thrace ( 353 – 352 BC ) . Most historians agree that Philip campaigned in Thrace in 353 BC , but what exactly he achieved is a matter of some confusion . As has been discussed , some , including Cawkwell and Sealey , place the Maroneia and Abdera campaign in 353 BC . Others suggest that , in a campaign whose details are essentially unknown , Philip defeated the central Thracian king , Amadokos , reducing him to the status of subject ally . Since the Maroneia and Abdera campaign took place in Amadokos ' s territory , it seems likely that , under either chronology , Philip campaigned against Amadokos in 353 BC . In the early part of 352 BC several key events had occurred in , or around Thrace which challenged Philip ' s influence in the region . The Athenian general Chares captured Sestos , on the Thracian Chersonese early in the year , probably taking the city from Kersebleptes . The Athenians had a long - standing interest in the Chersonese for strategic reasons , and it had formed a significant part of their ' Empire ' in the 5th century BC . Firstly , Athens depended largely on the import of grain from the Crimea for her food supply ; controlling the Chersonese helped to ensure that supplies could safely pass through the Hellespont . Secondly , the Chersonese was used as a place to settle the excess citizenry of Athens , usually in the form of cleruchies , colonies which were not politically independent of the mother city . After the capture of Sestos , Kersebleptes , who up until now had resisted Athenian attempts to reclaim the Chersonese , now came to terms with Athens . He was probably now worried about Philip ' s influence in the region , and thus sought to ally with the Athenians , giving them control of all the cities of the Chersonese except Cardia . Furthermore , the Chalkidian League also seems to have turned against Philip in 352 BC , presumably also concerned by his designs on their territory , and sought peace with Athens . Philip probably also campaigned in Thrace in late 352 BC , possibly after returning to Macedon from Thessaly . At this point , if not before , Philip defeated Amadokos and subjugated him , and possibly also expelled Cetriporis from his client kingship . During the campaign , Philip ' s army reached deep into Kersebleptes ' s territory and laid siege to the fortress of Heraion Teichos located somewhere near Perinthos , on the coast of the Propontis ( although Buckler places this siege in 353 BC ) . On learning of the siege , the Athenians voted to dispatch 40 triremes to oppose Philip . However , they then heard that Philip had died ( or had been taken ill ) , so the relief mission never actually sailed . It seems clear that Philip did fall ill during the campaign , but exactly how the campaign ended is unclear . It was probably at this time that Philip took Kersebleptes ' s son as a hostage to Pella , effectively ending Kersebleptes ' s freedom of action . The Olynthian War ( 349 – 348 BC ) . As discussed , the Chalkidian League had made peace with Athens in 352 BC , in clear breach of their alliance with Philip , due to their growing fear of Macedonian power . Cawkwell contends that from that moment on , Olynthus and the League were doomed . However , the next few years of Philip ' s reign appear to have been militarily quiet ; Diodorus does not mention any activity by Philip until 349 BC . Philip did not yet make any further efforts to intervene in the Sacred War , which was to rumble on until 346 BC . In the meantime , there may have been some unrest in Macedonia ; Philip executed one of his stepbrothers ( sons of Amyntas III ' s second wife ) , and two more fled to Olynthos . According to Justin , this provided Philip with the pretext of attacking Olynthos and the Chalkidian League . Philip finally began his campaign against the Chalkidian league in 349 BC , probably in July , when the Etesian winds would prevent Athens sending aid . Diodorus says that he started by besieging , capturing and razing the fortress of Zereia ( possibly Stageira ; otherwise unknown ) . Philip seems to have methodically worked his way around the 32 cities of the League , leaving Olynthos to the end . At least some cities submitted to him , including Toroni and Mecyberna , a small town which acted as the harbour of Olynthos , and having seen the fate of the cities which resisted Philip . By the spring of 348 BC , the western part of Chalkidiki had been lost , and the Olynthians resorted to ravaging their former territory . Finally , in probably June 348 BC , with all the other cities captured or in submission , Philip moved to attack Olynthus . According to Diodorus , there were two pitched battles against the Olynthians ; after being defeated twice , the Olynthians were then confined to the city . Two of the commanders of Olynthus , Euthycrates and Lasthenes , defected to Philip with 500 cavalry shortly before the siege . Diodorus therefore claims that the city fell by treachery ; certainly treachery was committed , but it is not clear that this is how the city was captured . Either way , by September the siege was over , and the Chalkidian league had been annihilated . Philip razed the city , and sold the remaining inhabitants into slavery ; the same fate awaited the other Chalkidian cities that had not submitted to him . Philip then incorporated Chalkidiki into the Macedonian state , distributing the land amongst his followers . Athens and the Olynthian War . When Philip began his attack in 349 BC , the Olynthians appealed to Athens for aid . In response , Demosthenes gave a series of speeches , now known as the " Olynthiacs " , encouraging the Athenians to resist Philip . The period from 351 BC to 346 BC marks the gradual ascendancy of Demosthenes in Athenian politics , as he become leader of the Athenian resistance to Philip . However , exactly when Demosthenes became important is disputed ; Cawkwell points out that the chance preservation of a good proportion of Demosthenes ' s speeches may make him seem more important than he was . In the end , the Athenians decided to send a force of 2 , 000 lightly armed mercenaries ( referred to in the sources as peltast s , even if strictly speaking , they were not ) , and 38 triremes to aid the Olynthians . Thirty of the triremes were already in service under Chares , possibly operating in the north Aegean ; the other 8 were to be crewed by Athenians citizens . However , it is not clear whether this force achieved anything . Later , in early 348 BC , the Olynthians appealed for help again . The Athenians sent Charidemus , a former general of Kersebleptes who had been adopted as an Athenian citizen , with 4 , 000 peltasts , 150 cavalry and 18 triremes ; of the triremes , 10 were probably already in his service , and the other 8 may have been those sent to Chares in 349 BC . Charidemus joined up with the Olynthians , and together they attacked the former territory of Olynthos in western Chalkidiki . Finally , just before the final siege of Olynthos started , the Olynthians appealed a last time for aid . The Athenians prepared to send a force of citizen hoplites , but they were delayed by the weather , probably due to the Etesian winds , and arrive too late to achieve anything . Euboea . Athens was prevented from sending more effective aid by events on Euboea in 348 BC . A pre - eminent politician from Chalcis , Callias sought unite the cities of Euboea in a new confederation , inevitably meaning the end of the hitherto strong Athenian presence on the island . Strategically , this was unacceptable for the Athenians . In 410 BC , the strait between Euboea and the mainland , the Euripos , was narrowed , and then bridged at Chalcis . If Euboea , and in particular Chalcis , was no longer controlled by Athens then Philip could potentially cross into Euboea from Thessaly , and then cross back into Boeotia via the bridge at Chalcis , thus outflanking Thermopylae . The whole Athenian strategy in the years after 352 BC therefore required that they hold Euboea . In early 348 BC the Athenians were distracted by events on Euboea , and were in no position to send much help to Olynthos . However , the expedition the Athenians sent to Euboea to try and maintain their position on the island was a disaster , and the Athenians had to seek peace with Chalcis , thereby effectively losing control of the island . It is possible that Philip actually incited the revolt on Euboea , though it considered more likely that this is a misreading of a speech of the Athenian politician Aeschines . End of the Sacred War ( 347 – 346 BC ) . The Athenian politician Philocrates had suggested offering Philip peace in 348 BC , during the Olynthian war . However , the Athenian assembly had effectively rejected this proposal by putting Philocrates on trial , and by the time he was cleared of the charges , it was too late to save Olynthos . The war between Athens and Philip thus continued through 347 BC , as did the Sacred War . In 347 BC , Philip sent privateers to attack Athenians colonies on various Aegean islands . Meanwhile , it was becoming clear that the Sacred War could only be ended by outside intervention . The Phocians had occupied several Boeotian cities , but were running out of treasure to pay their mercenaries ; conversely , the Thebans were unable to act effectively against the Phocians . The Phocian general Phalaikos was removed from his command in 347 BC , and three new generals appointed , who successfully attacked Boeotia again . The Thebans appealed to Philip for aid , and he sent a small force to their assistance . Philip sent force enough to honour his alliance with Thebes , but not enough to end the war — he desired the glory of ending the war personally , in the manner of his choosing , and on his terms ; In early 346 BC , Philip let it be known that he intended to march south with the Thessalians , though not where or why . The Phocians thus made plans to defend Thermopylae , and requested assistance from the Spartans and the Athenians , probably around the 14th of February . The Spartans dispatched Archidamus III with 1 , 000 hoplites , and the Athenians ordered everyone eligible for military service under the age of 40 to be sent to the Phocians ' aid . However , between the Phocians ' appeal and the end of the month , all plans were upset by the return of Phaleacus to power in Phocis ; the Athenians and the Spartans were subsequently told that they would not be permitted to defend Thermopylae . It is not clear from the ancient sources why Phalaikos was returned to power , not why he adopted this dramatic change of policy . Cawkwell suggests , based on remarks of Aeschines that the Phocian army restored Phalaikos because they had not been properly paid , and further that Phalaikos , realizing that the army could not be paid and that the Phocians could no longer hope to win the war , decided to try and negotiate a peace settlement with Philip . Peace with Athens . When the Athenians received this news , they rapidly changed policy . If Thermopylae could no longer be defended , then Athenian security could no longer be guaranteed . By the end of February , the Athenians had dispatched an embassy , including Philocrates , Demosthenes and Aeschines , to Philip to discuss peace between Athens and Macedon . The embassy had two audiences with Philip , in which each side presented their proposals for the terms of the peace settlement . The embassy then returned to Athens to present the proposed terms to the Athenian Assembly , along with a Macedonian embassy to Athens , empowered by Philip to finalize an agreement . The Athenians debated the peace treaty in April and tried to propose a common peace in which all Greek states could partake ( including Phocis ) . However , Demosthenes ( at this point a strong proponent of peace ) persuaded the Assembly that Philip would never agree to such a peace , and that Athens ' s vulnerable position meant that they had little choice but to accept Philip ' s terms . On 23 April , the Athenians made swore to the terms of the treaty which is now known as the Peace of Philocrates in the presence of the Macedonian ambassadors . Amongst the principal terms were that Athens become Philip ' s ally , and that they forever renounce their claim to Amphipolis . End of Thracian independence . Following the first Athenian embassy to Macedon , Philip went on campaign against Kersebleptes . Details of the campaign are scarce , but it seems that Philip easily captured the Thracian treasury on the " Sacred Mountain " . Then , rather than deposing Kersebleptes , he made him a subject ally , in the same manner as his brother Amadokos . Settlement of the Sacred War . After agreeing to the peace terms with Macedonian ambassadors in April , the Athenians dispatched a second embassy to Macedon , to extract the peace oaths from Philip . When they arrived , the Athenians ( again including Demosthenes and Aeschines ) were rather surprised to find embassies from all the principal combatants in the Sacred War were also present , in order to discuss a settlement to the war . When Philip returned from Thrace he received all these embassies . The Thebans and Thessalians requested that he take the leadership of Greece , and punish Phocis ; conversely , the Phocians , supported by the Spartans and the Athenian delegations , pleaded with Philip not to attack Phocis . Philip , however , delayed making any decisions ; " [ he ] sought by every means not to reveal how he intended to settle things ; both sides were privately encouraged to hope that he would do as they wanted , but both were bidden not to prepare for war ; a peacefully arranged concordat was at hand " ; he also delayed taking the oaths to the Peace of Philocrates . Military preparations were ongoing in Pella during this period , but Philip told the ambassadors that they were for a campaign against Halus , a small Thessalian city which held out against him . He departed for Halus before making any pronouncements , compelling the Athenian embassy to travel with him ; only when they reached Pherae did Philip finally take the oaths , enabling the Athenian ambassadors to return home . It was now that Philip applied the " coup de grace " . He had persuaded the Athenians and other Greeks that he and his army was heading for Halus , but it seems certain that he also sent other units straight to Thermopylae . All of central and southern Greece was now at Philip ' s mercy , and the Athenians could not now save Phocis even if they abandoned the peace . Philip could be certain of dictating the terms of the end of the Sacred War , since he could now use force against any state that did not accept his arbitration . He began by making a truce with Phalaikos on 19 July ; Phalaikos surrendered Phocis to him , in return for being allowed him to leave , with his mercenaries , and go wherever he wished . Philip then declared that the fate of Phocis would not be decided by him , but by the Amphictyonic Council . However , it is clear that Philip was dictating the terms behind the scenes ; allowing the Amphictyons the formal responsibility allowed him to dissociate himself from the terms in the future . In return for ending the war , Macedon was made a member of the Amphictyonic council , and given the two votes which had been stripped from Phocis . This was an important moment for Philip , since membership of the Ampictyony meant that Macedon was now no longer a ' barbarian ' state in Greek eyes . The terms imposed on Phocis were harsh , but realistically Philip had no choice but to impose such sanctions ; he needed the support of the Thessalians ( sworn enemies of Phocis ) , and could not risk losing the prestige that he had won for his pious conduct during the war . Aside from being expelled from the Amphictyonic council , all the Phocian cities were to be destroyed , and the Phocians settled in ' villages ' of no more than fifty houses ; the money stolen from the temple was to be paid back at a rate of 60 talents per year ; the Phocians were not , however , destroyed , and their retained their land . The Athenians , having made peace with Philip , were not penalised by the Amphictyonic council , and the Spartans also seem to have escaped lightly . Philip presided over the Amphictyonic festival in the autumn , and then much to the surprise of the Greeks , he went back to Macedon and did not return to Greece for seven years . He did however retain his access , by garrisoning the closest town to Thermopylae , Nicaea with Thessalian troops . Summary to 346 BC . 346 BC was another remarkable year for Philip . The city - states of Greece had exhausted themselves in the previous years , and Philip was therefore the only power capable of finally ending the Sacred War . Ultimately , once in control of Thermopylae , this military strength allowed him to settle the war by mere threat of force . Philip undoubtedly intended to settle the war even before the Thessalians and Thebans requested that he do so , and the terms on which the war was concluded were presumably much as he would have desired ; coming to a separate peace with Athens was a bonus . Philip was , through his membership of the Amphictyonic council , now legitimized as a " true " Greek ; and by the prestige he had gained for his pious conduct on behalf of Apollo , and by his military strength , he was now the " de facto " " leader " of the Greek city - states . Hornblower therefore suggests that Philip was the only real victor in the Sacred War . Furthermore , Philip ' s domination of the northern Greece and the north Aegean was now almost complete , after his success in the Olynthian War and his subjugation of Kersebleptes . Diodorus sums up Philip ' s achievements in 346 BC : There has been much debate amongst historians about Philip ' s motives and aims in 346 BC , with particular regard to Athens . Although Philip had made peace and alliance with Athens prior to his settlement of the Sacred War , they failed to send him troops he requested under the terms of the alliance . Although these troops were not ultimately needed by Philip , the Athenian failure to honour the terms gave Philip reasonable grounds for war . However , even when in possession of Thermopylae , he made no hostile moves towards Athens , and still prevented any punishment being meted on Athens by the Amphictyonic council . Why was Philip so lenient towards Athens ? Cawkwell suggests that Philip was already beginning to contemplate a campaign against Persia in 346 BC ( as tentatively suggested by Diodorus ) , for which purposes he desired the use of the powerful Athenian navy ; hence his request for alliance , and his on - going patience with Athens . This may also provide another explanation for Philip ' s use of the Amphictyonic council to formally settle the Sacred War ; if he was to campaign in Asia , he needed Greece to be peaceful , and a peace imposed through a pan - Greek organisation ( backed with the threat of Macedonian intervention ) , was more likely to succeed than one directly imposed by Macedon . Reorganisation and retrenchment ( 345 – 342 BC ) . The next year , Philip returned to the ongoing business of restructuring Macedon . Justin reports that after returning to Macedon , he began transplanting parts of the population to new locations , in particular strengthening the cities of Macedon . This was probably to increase the security of the population , and promote trade ; Alexander the Great would later recall that his father had brought " the Macedonians down from the hills to the plains " . Illyria ( 345 BC ) . Philip then went on campaign against the Illyrians , particularly Pleuratus , whose kingdom probably lay along the Drin river in modern Albania . During the campaign , Philip suffered a smashed shin - bone , and was only saved from death by the bravery of his Companion cavalry ( 150 of whom were wounded in the process ) . Philip did not campaign in 344 or 343 BC , which may have been due to the effects of this severe injury . Instead , Philip contended himself with reorganising Thessaly in 344 BC , reinstating the ancient fourfold " Tetrarchic " administration system . Molossia and Cassopaea ( 342 BC ) . The Molossian kingdom of Epirus had been an important subject ally of Macedon since 350 BC , when Philip had taken the son of king Arybbas , Alexander hostage . During this time at court , Alexander ( brother of Philip ' s wife Olympias , had grown into an admirer of Philip , and Philip therefore decided to replace Arybbas with Alexander . The exact date this occurred is unclear ; Cawkwell suggests this happened in early 342 BC , when Alexander would have been 20 , as a prelude to his Thracian campaign . Arybbas went into exile in Athens , where he was promised help to regain his kingdom ; however , Alexander would remain on the throne ( and loyal to Philip ) until his death in 334 BC . Philip certainly campaigned against the Epirote Cassopaeans in early 342 BC , taking control of three cities to secure the southern regions of his kingdom . Thrace ( 342 – 340 BC ) . In approximately June 342 BC , Philip set off on what must have been a long - planned expedition into Thrace . The campaign was to last for two years , but other than that his forces were large , and that he fought several battles , the ancient sources contain very few details . Undoubtedly Philip ' s primary aim was to depose Kersebleptes , who according to Diodorus had been causing problems for the Greeks on the Chersonese , once and for all . Philip ended the campaign by marrying the daughter of a king of the Getae , which has been taken to suggest that Philip campaigned not just in Thrace , but in the valley of the Hebrus , and north of the Great Balkan range of mountains , near the Danube . During the campaign , Philip founded several cities , most notably Philippopolis on the site of the old Thracian fort of Eumolpia . A tithe was levied on the Thracians , and the new post of " general in charge of Thrace " may have been established at this time , effectively governor of a new Macedonian province of Thrace . To the north of this pacified region , the Thracians were left mostly independent , under their own kings , who were subject to Philip . Cawkwell rates this extended campaign as one of Philip ' s major achievements , given the terrain and severe winter conditions . Perinthos and Byzantion ( 340 – 339 BC ) . At the end of his Thracian campaign , Philip moved against the city of Perinthos , formerly his ally . Diodorus says that this was because the city had begun to oppose him , and favour the Athenians ; however , from Athenian sources , there is no indication that this was the case . One possible explanation is that Perinthos had refused to send aid to Philip during the Thracian campaign , and it was for this reason he decided to attack it . Either way , since Perinthos was a Greek city , Philip ' s actions gave the Athenian war - party the excuse it had been looking for to disrupt the peace Philip had wrought in Greece , thereby starting a new phase in the wars . Breakdown of the Peace . Although Demosthenes had been a principal architect of the Peace of Philocrates , almost as soon as it was made , he wished to be rid of it . Over the next few years , Demosthenes became leader of the " war - party " in Athens , and at every opportunity he sought to undermine the peace : " His method was simple and effective . He kept hammering away at untruths until enough Athenians came to believe them . " Demosthenes believed that all Philip ' s successes were due to his bribery and corruption of the Greeks , a view which , although there is little evidence for it , became commonplace until re - examined by modern historians . Conversely , there was also a substantial body of feeling in Athens , led by Aeschines , that the peace should be maintained and developed . From 343 BC onwards , in order to try and disrupt the peace , Demosthenes and his followers used every expedition and action of Philip to argue that he was breaking the peace . Finally , in 341 BC , matters began to come to a head . Athens sent out new settlers to the cleruchs on the Chersonsese under the command of Diopithes , who proceeded to ravage the territory of Cardia , and ally of Philip . Philip therefore wrote to the Athenians to demand that they desist , but in his speech ' On the Chersonese ' , Demosthenes persuaded the Athenians that since Athens was effectively at war with Philip anyway , there was no need to do what Philip asked ; Diopithes therefore continued to cause trouble in Thrace . Then , in the Third Philippic of approximately May 341 BC , Demosthenes accused Philip of breaking the peace by intervening in the affairs of Euboea . Finally , in the Fourth Philippic delivered later in 341 BC , Demosthenes argued that Athens should send an embassy to the Persian king , requesting money for a forthcoming war with Macedon . The embassy was sent , much to Philip ' s anger , but was sharply rebuffed by the Persians . Perinthos . Against this fraught background , Philip started the siege of Perinthos in July 340 BC . Perinthos occupied a strong position on a hill rising to 56 meters , with its own port . Philip did not have a large enough fleet to blockade the port , meaning that Perinthos could be supplied from outside ; Philip would therefore have to assault the city . Philip ' s engineers constructed siege towers ( some allegedly 80 cubit s high ) , battering rams and mines for the assault , and in a short time , a section of the wall was breached . However , fighting uphill through the city proved difficult , with the rings of houses providing impromptu defence lines for the Perinthians . Aid , both material and military now began arriving at Perinthos ; the Persian king ordered his satraps on the coast of Asia Minor to send money , food and weapons to the city , while the Byzantians sent a body of soldiers and their best generals . Byzantion . The Byzantians ' actions meant that they too were now at war with Philip . He continued the siege of Perinthos , but now ( September ) sent half his army to besiege Byzantion . Byzantion was a more important city for Philip , because of its control of the Bosphorus ; Demosthenes was determined to prevent the capture of the city , and went on an embassy to Byzantion , which agreed to form an alliance with Athens . The Athenians general Chares was already in the vicinity with 40 ships , and was sent to support Byzantion ; furthermore , Byzantion ' s other allies , Chios , Rhodes and Kos also sent aid to the city . Since he still did not control the seas , Philip already faced a difficult task to besiege Byzantion , made all the more difficult by the outside support . Again , Philip ' s engineers set to work , and created a breach ; a night assault was then made , but was repulsed . Frustrated in the two sieges , Philip now lost patience with the Athenians , and wrote to them , declaring war . In Athens , Demosthenes proposed that the Athenians should respond by declaring war on Philip ; the motion was passed , and the stone tablet recording the peace of Philocrates destroyed . The Athenians prepared another fleet under the command of Phocion , and dispatched it to Byzantion . The first act in this new war was Philip ' s seizure of 230 grain ships that had been waiting on the far side of the Bosphorus to be convoyed past Byzantion by Chares . He used the grain for his own supplies and the ships ' timbers to build siege engines . However , what happened over the next few months is unclear ; although to judge by Philip ' s activities in 339 BC , he cannot have spent more than 3 months besieging Byzantion . The walls of Byzantion were very tall and strong , and the city was full of defenders , and well supplied by sea ; it is therefore possible Philip gave up on the siege , rather than waste time and men trying to assault it . The Greeks viewed this , and the abandonment of the siege of Perinthos , as a glorious victory . Philip ' s motives are as unclear as ever ; Cawkwell suggests that , since he was now at war with Athens , he decided to go straight to the root of the problem , rather than be detained at Byzantion . Philip ' s final campaigns ( 339 – 338 BC ) . Scythia . As a prelude to his planned campaign in Greece , Philip went on campaign in the winter of 339 BC , against the Scythians living south of the Danube , near the river ' s mouth ( in Dobruja ) . He defeated them in battle , taking many captive , and built a statue of Heracles to commemorate his victory . He then marched through the territory of the Triballi in a demonstration of force , which probably lay upstream along the course of the Danube . During a skirmish , he was severely wounded in the leg when a spear passed through it and killed the horse he was riding . Recovering from this wound may have delayed Philip ' s campaign in Greece , since he did not set off until the autumn of 339 BC . Fourth Sacred War . Philip ' s campaign in Greece became linked with a new , fourth , Sacred War . The citizens of Amphissa in Ozolian Locris had begun cultivating land sacred to Apollo on the Crisaean plain south of Delphi ; after some internal bickering the Amphictyonic council decided to declare a sacred war against Amphissa . A Thessalian delegate proposed that Philip should be made leader of the Amphictyonic effort , which therefore gave Philip a pretext to campaign in Greece ; it is , however , probable that Philip would have gone ahead with his campaign anyway . At the start of the 339 BC , the Thebans had seized the town of Nicaea near Thermopylae , which Philip had garrisoned in 346 BC . Philip does not appear to have treated this as a declaration of war , but it nevertheless presented him with a significant problem , blocking the main route into Greece . However , a second route into central Greece was available . In 480 BC , during the Battle of Thermopylae , the Persian king Xerxes had sent his army via a mountain track ( the " Anopea " ) to outflank the pass . From this track , on the western side of Mount Callidromus , another road led off and descended in Phocis . In 480 BC , 1000 Phocian troops were stationed above Thermopylae , guarding this road , and preventing the Persian marching into Phocis ( though they notably failed to prevent the Persians using " Anopea " ) . However , in 339 BC , the Greeks had either forgotten the existence of this road , or believed that Philip would not use it ; the subsequent failure to guard this road allowed Philip to slip into central Greece unhindered . Philip ' s relatively lenient treatment of the Phocians in 346 BC now bore fruit . Reaching Elatea , he ordered the city to be re - populated , and during the next few months the whole Phocian confederation was restored to its former state . This provided Philip with a base in Greece , and new , grateful allies in the Phocians . Philip probably arrived in Phocis in November 339 BC , but the decisive phase of the campaign did not occur until August 338 BC . During this period Philip discharged his responsibility to the Amphicytonic council by settling the situation in Amphissa . He tricked a force of 10 , 000 mercenaries who were guarding the road from Phocis to Amphissa into abandoning their posts , then took Amphissa and expelled its citizens , turning it over to Delphi . He probably also engaged in diplomatic attempts to try and avoid further conflict in Greece , although if so , he was unsuccessful . Alliance between Athens and Thebes . When news first arrived that Philip was in Elatea , just three days march away , there was panic in Athens . In what Cawkwell describes as his proudest moment , Demosthenes alone counselled against despair , and proposed that the Athenians should seek an alliance with the Thebans ; his decree was passed , and he was sent as ambassador . Philip had also sent an embassy to Thebes , requesting that the Thebans join him , or at least allow him to pass through Boeotia unhindered . Since the Thebans were still not formally at war with Philip , they could have avoided the conflict altogether . However , in spite of Philip ' s proximity , and their traditional enmity with Athens , they chose to ally with the Athenians , in the cause of liberty for Greece . The Athenian army had already pre - emptively been sent in the direction of Boeotia , and was therefore able to join the Thebans within days of the alliance being agreed . The details of the campaign leading up to the decisive Battle of Chaeronea are almost completely unknown . Philip was presumably prevented from entering Boeotia by way of Mount Helicon , as the Spartans had done in the run - up to the Battle of Leuctra ; or by any of the other mountain passes . There were certainly some preliminary skirmishes ; Demonsthenes alludes to a " winter battle " and " battle on the river " in his speeches , but no other details are preserved . Finally , in August 338 BC , Philip ' s army marched straight down the main road from Phocis to Boeotia , to assault the allied Greek army defending the road at Chaeronea . Chaeronea . The Greek army had taken up a position near Chaeronea , astride the main road . On the left flank , the Greek line lay across the foothills of Mount Thurion , blocking the side - road that led to Lebedea , while on the right , the line rested against the Kephisos river , near a projecting spur of Mount Aktion . The allied Greek army included contingents from Achaea , Corinth , Chalcis , Epidaurus , Megara and Troezen , with the majority of troops being supplied by Athens and Thebes . The Athenian contingent was led by the generals Chares and Lysicles , and the Thebans by Theagenes . No source provides exact numbers for the Greek army ; the modern view is that the Greek numbers were approximately equal to those of the Macedonians , who according to Diodorus numbered roughly 30 , 000 infantry and 2 , 000 cavalry . Philip took command of the right wing of the Macedonian wing and placed his 18 - year - old son Alexander ( the future Alexander the Great ) in command of the left wing , accompanied by a group of Philip ' s experienced generals . Details of the battle itself are scarce , with Diodorus providing the only formal account . He says that " once joined , the battle was hotly contested for a long time and many fell on both sides , so that for a while the struggle permitted hopes of victory to both . " He then recounts that the young Alexander , " his heart set on showing his father his prowess " succeeding in rupturing the Greek line aided by his companions , and eventually put the Greek right wing to flight ; meanwhile , Philip advanced in person against the Greek left and also put it to flight . This brief account can be filled out , if Polyaenus ' s anecdotes related to the battle ( found in his work " Strategems " ) are to be believed . Polyaenus ' s accounts have led some modern historians to tentatively propose the following synthesis of the battle . After the general engagement had been in progress for some time , Philip had his army perform a wheeling manoeuver , with the right wing withdrawing , and the whole line pivoting around its centre . At the same time , wheeling forward , the Macedonian left wing attacked the Thebans on the Greek right and punched a hole in the Greek line . On the Greek left , the Athenians followed Philip , their line becoming stretched and became disordered ; the Macedonians then turned , attacked and routed the tired and inexperienced Athenians . The Greek right wing , under the assault of the Macedonian troops under Alexander ' s command , then also routed , ending the battle . Diodorus says that more than 1 , 000 Athenians died in the battle , with another 2 , 000 taken prisoner , and that the Thebans fared similarly . Cawkwell suggests that this was one of the most decisive battles in ancient history ; since there was now no army which could prevent Philip ' s advance , the war effectively ended . Settlement of Greece and League of Corinth ( 337 – 336 BC ) . In the aftermath of Chaeronea , records show desperate attempts in Athens and Corinth to re - build the city walls , as they prepared for Philip to lay siege to them . However , Philip had no intention of besieging any city , nor indeed of conquering Greece . He wanted the Greeks as his allies for his planned campaign against the Persians , and he wanted to leave a stable Greece in his rear when he went on campaign ; further fighting was therefore contrary to his aims . Philip marched first to Thebes , which surrendered to him ; he expelled the Theban leaders who had opposed him , recalled those pro - Macedonian Thebans who had previously been exiled , and installed a Macedonian garrison . He also ordered that the Boeotian cities of Plataea and Thespiae , which Thebes had destroyed in previous conflicts , be re - founded . Generally , Philip treated the Thebans severely , making them pay for the return of their prisoners , and even to bury their dead ; he did not , however , dissolve the Boeotian confederacy . By contrast , Philip treated Athens very leniently indeed ; although the Second Athenian Confederacy was dissolved , the Athenians were allowed to keep their colony on Samos , and their prisoners were freed without ransom . Philip ' s motives are not entirely clear , but one likely explanation is that he hoped to use the Athenian navy in his campaign against Persia , since Macedon did not possess a substantial fleet ; he therefore needed to remain on good terms with the Athenians . Philip also made peace with the other combatants ; Corinth and Chalcis , which controlled important strategic locations both received Macedonian garrisons . He then turned to deal with Sparta , which had not taken part in the conflict , but was likely to take advantage of the weakened state of the other Greek cities to try and attack its neighbours in the Peloponnese . The Spartans refused Philip ' s invitation to engage in discussions , so Philip ravaged Lacedaemonia , but did not attack Sparta itself . League of Corinth . Philip seems to have moved around Greece in the months after the battle , making peace with the states that opposed him , dealing with the Spartans , and installing garrisons ; his movements also probably served as a demonstration of force to the other cities , that they should not try to oppose him . In mid 337 BC , he seems to have camped near Corinth , and began the work to establish a league of the Greek city - states , which would guarantee peace in Greece , and provide Philip with military assistance against Persia . The result , the League of Corinth , was formed in the latter half of 337 BC at a congress organised by Philip . All states signed up to the league , with the exception of Sparta . The principal terms of the concord were that all members became allied to each other , and to Macedon , and that all members were guaranteed freedom from attack , freedom of navigation , and freedom from interference in internal affairs . Philip , and the Macedonian garrisons installed in Greece , would act as the ' keepers of the peace ' . At Philip ' s behest , the synod of the League then declared war on Persia , and voted Philip as " Strategos " for the forthcoming campaign . War with Persia and death of Philip ( 336 BC ) . In 336 BC , whilst the invasion of Persia was in its very early stage , Philip was assassinated by the captain of his bodyguard , Pausanias whilst attending the wedding of his daughter by Olympias , Cleopatra , to Olympias ' s brother , Alexander I of Epirus in Aegea . . Philip ' s son Alexander was proclaimed king by the Macedonian army and by the Macedonian noblemen . Accesion of Alexander and Balkan campaigns ( 336 – 335 BC ) . Alexander began his reign by having his potential rivals to the throne murdered . He had his cousin , the former Amyntas IV , executed , as well as having two Macedonian princes from the region of Lyncestis killed , while a third , Alexander Lyncestes , was spared . Olympias had Cleopatra Eurydice and her daughter by Philip , Europa , burned alive . When Alexander found out about this , he was furious with his mother . Alexander also ordered the murder of Attalus , who was in command of the advance guard of the army in Asia Minor . Attalus was at the time in correspondence with Demosthenes , regarding the possibility of defecting to Athens . Regardless of whether Attalus actually intended to defect , he had already severely insulted Alexander , and having just had Attalus ' s daughter and grandchildren murdered , Alexander probably felt Attalus was too dangerous to leave alive . Alexander spared the life of his half - brother Arrhidaeus , who was by all accounts somewhat mentally disabled , possibly as a result of poisoning by Olympias . News of Philip ' s death roused many states into revolt , including Thebes , Athens , Thessaly , and the Thracian tribes to the north of Macedon . When news of the revolts in Greece reached Alexander , he responded quickly . Though his advisors advised him to use diplomacy , Alexander mustered the Macedonian cavalry of 3 , 000 men and rode south towards Thessaly , Macedon ' s neighbor to the south . When he found the Thessalian army occupying the pass between Mount Olympus and Mount Ossa , he had the men ride over Mount Ossa . When the Thessalians awoke the next day , they found Alexander in their rear , and promptly surrendered , adding their cavalry to Alexander ' s force , as he rode down towards the Peloponnesus . Alexander stopped at Thermopylae , where he was recognized as the leader of the Amphictyonic League before heading south to Corinth . Athens sued for peace and Alexander received the envoy and pardoned anyone involved with the uprising . At Corinth , he was given the title " Hegemon " , and like Philip , appointed commander of the forthcoming war against Persia . Balkan campaign . Before crossing to Asia , Alexander wanted to safeguard his northern borders ; and , in the spring of 335 BC , he advanced to suppress several apparent revolts . Starting from Amphipolis , he first went east into the country of the " Independent Thracians " , and at Mount Haemus , the Macedonian army attacked and defeated a Thracian army manning the heights . The Macedonians marched on into the country of the Triballi , and proceeded to defeat the Triballian army near the Lyginus river ( a tributary of the Danube ) . Alexander then advanced for three days on to the Danube , encountering the Getae tribe on the opposite shore . Surprising the Getae by crossing the river at night , he forced the Getae army to retreat after the first cavalry skirmish , leaving their town to the Macedonian army . News then reached Alexander that Cleitus , King of Illyria , and King Glaukias of the Taulanti were in open revolt against Macedonian authority . Marching west into Illyria , Alexander defeated each in turn , forcing Cleitus and Glaukias to flee with their armies , leaving Alexander ' s northern frontier secure . While he was triumphantly campaigning in the north , a rumour of his death caused the Thebans and Athenians to rebel against Macedonian hegemony once more . Alexander reacted immediately but , while the other cities hesitated when he advanced into Greece , Thebes decided to resist with the utmost vigor . However , the resistance was useless , and the city was captured and then razed to the ground , and its territory was divided between the other Boeotian cities . The end of Thebes cowed Athens into submission , leaving all of Greece at least outwardly at peace with Alexander . With Macedon ' s vassals and allies once again peaceable , Alexander was finally free to take control of the stalled war with Persia , and in early 334 BC he crossed with an army of 42 , 000 men into Asia Minor . Alexander ' s campaigns in Asia . Alexander ' s 10 - year campaign in Asia , and the Macedonian conquest of the Persian empire were to become the stuff of legend . The Macedonian army campaigned in Asia Minor , the Levant , Egypt , Assyria , Babylonia and Persia , winning notable battles at the Granicus , the Issus and Gaugamela , before the final collapse of Darius ' s rule in 330 BC . Alexander thus became ruler of the extensive Persian domains , although his rule over most of the territory was far from secure . Alexander continued campaigning in central Asia in the following years , before crossing into the Indian sub - continent . However , the Macedonian army became increasingly unhappy , and eventually mutinied , forcing Alexander to turn back . Alexander spent his final years attempting to consolidate his empire and planning future campaigns but , probably exhausted by years of hard campaigning , he died in Babylon in 323 BC . Aftermath . Alexander ' s early death and lack of obvious heir quickly led to the end of the Argead dynasty , and the collapse of the new - found Macedonian empire , as his generals fought over the spoils .