Battle of Crocus Field The Battle of Crocus Field ( ) ( also known as the " Battle of Volo " ) was a battle in the Third Sacred War , fought between the armies of Phocis , under Onomarchos , and the combined Thessalian and Macedonian army under Philip II of Macedon . In the bloodiest battle recorded in Ancient Greek history , the Phocians were decisively defeated by Philip ' s forces . Philip ' s victory secured his appointment as ruler of Thessaly , marking an important step in the rise of Macedon to political ascendancy in Ancient Greece . Opinion amongst historians is divided as to the year of the battle ; some favour 353 BC , and others 352 BC . Sources and Chronology . The ancient sources for the Third Sacred War are scant , and generally lacking in firm chronological information . 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 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 be 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 Third Sacred War therefore contains many gaps . Beyond Diodorus , further details of the Sacred War 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 circumspection ; 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 " . Nevertheless , their allusions to contemporary or past events indicates some of the gaps in Diodorus ' s account , and helps with the arrangement of the chronology . The accounts of Diodorus , Demosthenes and Aeschines can be further supplemented by fragments of otherwise lost histories ( such as that by Theopompus ) and by contemporary epigraphic sources . Modern historians ' dates for the war have been hotly debated , and there is 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 . A combination of evidence suggests that Pammenes met with Philip at Maroneia in Thrace , in 355 BC , presumably on his outward journey to Asia . Buckler , the only historian to produce a systematic study of the sacred war , therefore places Neon earlier in 355 BC . Other historians have placed Neon in 354 BC , since 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 . 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 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 . 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 , the - city state of Pherae had allied itself with the Phocians . In either 354 or 353 BC , the nobility of the Thessalian city of Larissa appealed to Philip to help them defeat the Pheraeans . 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 . 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 . 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 " . 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 . 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 . Prelude . Both Buckler and Cawkwell suggest that Philip besieged the strategic port of Pagasae ( effectively the harbour of Pherae ) before the Battle of Crocus Field . By taking Pagasae , it is probable that Philip intended to prevent it being reinforced by sea ; Buckler suggests that Philip had learnt his lesson from the previous campaign , and wanted to cut Pherae off from outside help before attacking it . Meanwhile , Onomarchus returned to Thessaly to try to preserve the Phocian ascendancy there , with approximately the same force as during the previous year . Furthermore , the Athenians dispatched Chares with a substantial fleet to help their Phocian allies , seeing the opportunity to strike a decisive blow against Philip . The Phocians and Athenians probably intended to rendezvous at Pagasae , since it was the only harbour the Athenian fleet could use , and since Philip was there anyway . Battle . Subsequent events are unclear , but a battle was fought between the Macedonians and the Phocians , probably as Philip tried to prevent the Phocians joining 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 , probably in the vicinity of Pagasae . The ' Crocus Field ' in Thessaly matches this description , and the battle is therefore now known as the Battle of Crocus Field ; however , this plain is so large that firmly identifying the battle - site has proved impossible . Philip sent his men into battle wearing crowns of laurel , the symbol of 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 , troubled by their guilty consciences . In the ensuing battle , the bloodiest recorded in ancient Greek history , Philip won a decisive victory over the Phocians . The battle seems to have been won by superior numbers and by the valour of Philip ' s cavalry . Fleeing from defeat , the Phocians ran to the sea , where Chares ' fleet had arrived during the battle , but many men were killed during the pursuit , or drowned as they tried to reach the ships . 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 than alive . . . Dreadful indeed was the punishment , but it was entirely consistent with Philip ' s role as Apollo ' s champion " . Aftermath . 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 . The tyrants of Pherae , rather than suffer the fate of Onomarchos , struck a bargain with Philip , and in return for handing Pherae over to Philip , were allowed , along with 2000 of their mercenaries , to go to Phocis . Philip spent some time reorganising Thessaly , and once satisfied , he 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 was 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 . 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 . Meanwhile , the Phocians regrouped under Onomarchos ' s brother , Phallyos . After the huge Phocian defeats at Neon and Crocus Field , Phallyos had to resort to doubling the pay for mercenaries , in order to attract enough to replenish his army . Despite their defeats however , the majority of the Phocians were still in favour of continuing the war . Over the winter of that year , Phallyos engaged in diplomatic efforts to gather more support from Phocis ' s allies , and succeeding in widening the theatre of conflict in the next campaigning season . Uniquely in Greek history , the Phocians were able to absorb huge losses in manpower , thanks to their pillaging of Temple of Apollo , a factor which was to contribute to the war dragging on indecisively until 346 BC .