Caesar ' s invasions of Britain In the course of his Gallic Wars , Julius Caesar invaded Britain twice : in 55 and 54 BC . The first invasion , in late summer , may have been intended as a mere reconnaissance - in - force expedition , or as a full - scale invasion — but if the latter , it was unsuccessful . It gained the Romans little else besides a beachhead on the coast of Kent . The second invasion achieved more : the Romans installed a king , Mandubracius , who was friendly to Rome , and they forced the submission of Mandubracius ' s rival , Cassivellaunus . No territory was conquered and held for Rome ; instead , all Roman - occupied territory was restored to the allied Trinovantes , along with the promised tribute of the other tribes in what is now eastern England . Britain before Caesar . Britain had long been known to the classical world as a source of tin . One hypothesis is that the name " Britain " is derived from a Phoenician word , " Baratanac " , that meant " Land of Tin " ; alternatively , it may have derived from a Brythonic word , such as Old Welsh " Priten " . The coastline had been explored by the Greek geographer Pytheas in the 4th century BC , and may have been explored even earlier , in the 5th , by the Carthaginian sailor Himilco . But to many Romans , the island , lying as it did beyond the Ocean at what was to them the edge of the " known world , " was a land of great mystery . Some Roman writers even insisted that it did not exist , and dismissed reports of Pytheas ' s voyage as a hoax . Britain during the reign of Julius Caesar had an Iron Age culture , with an estimated population of between one and four million . Archaeological research shows that its economy was broadly divided into lowland and highland zones . In the lowland southeast , large areas of fertile soil made possible extensive arable farming , and communication developed along trackways , such as the Icknield Way , the Pilgrims ' Way and the Jurassic Way , and navigable rivers such as the Thames . In the highlands , north of the line between Gloucester and Lincoln , arable land was available in only isolated pockets , so pastoral ism , supported by garden cultivation , was more common than settled farming , and communication was more difficult . Settlements were generally built on on high ground and fortified , but in the southeast , " oppida " had begun to be established on lower ground , often at river crossings , suggesting that trade was becoming more important . Commercial contact between Britain and the continent had increased since the Roman conquest of Transalpine Gaul in 124 BC , and Italian wine was being imported via the Armorica n peninsula , much of it arriving at Hengistbury Head in Dorset . Caesar ' s written account of Britain says that the Belgae of northeastern Gaul had previously conducted raids on Britain , establishing settlements in some of its coastal areas , and that within living memory Diviciacus , king of the Suessiones , had held power in Britain as well as Gaul . British coinage from this period shows a complicated pattern of settlement . The earliest Gallo - Belgic coins that have been found in Britain date to before 100 BC , perhaps as early as 150 BC , were struck in Gaul , and have been found mainly in Kent . Later coins of a similar type were struck in Britain and are found all along the south coast as far west as Dorset . It appears that Belgic settlement was concentrated on the southeastern coast , although their influence spread further west and inland , perhaps through chieftains establishing political control over the native population . First invasion ( 55 BC ) . Planning and reconnaissance . Caesar claimed that , in the course of his conquest of Gaul , the Britons had supported the campaigns of the mainland Gauls against him , with fugitives from among the Gallic Belgae fleeing to Belgic settlements in Britain , and the Veneti of Armorica , who controlled seaborne trade to the island , calling in aid from their British allies to fight for them against Caesar in 56 BC . Strabo says that the Venetic rebellion in 56 BC had been intended to prevent Caesar from travelling to Britain and disrupting their commercial activity , suggesting that the possibility of a British expedition had already been considered by then . In late summer , 55 BC , even though it was late in the campaigning season , Caesar decided to make an expedition to Britain . He summoned merchants who traded with the island , but they were unable or unwilling to give him any useful information about the inhabitants and their military tactics , or about harbours he could use , presumably not wanting to lose their monopoly on cross - channel trade . He sent a tribune , Gaius Volusenus , to scout the coast in a single warship . He probably examined the Kent coast between Hythe and Sandwich , but was unable to land , since he " did not dare leave his ship and entrust himself to the barbarians " , and after five days returned to give Caesar what intelligence he had managed to gather . By then , ambassadors from some of the British states , warned by merchants of the impending invasion , had arrived promising their submission . Caesar sent them back , along with his ally Commius , king of the Gallic Atrebates , to use their influence to win over as many other states as possible . He gathered a fleet consisting of eighty transport ships , sufficient to carry two legions ( Legio VII and Legio X ) , and an unknown number of warships under a quaestor , at an unnamed port in the territory of the Morini , almost certainly Portius Itius ( Boulogne ) . Another eighteen transports of cavalry were to sail from a different port , probably Ambleteuse . These ships may have been trireme s or bireme s , or may have been adapted from Venetic designs Caesar had seen previously , or may even have been requisitioned from the Veneti and other coastal tribes . Clearly in a hurry , Caesar himself left a garrison at the port and set out " at the third watch " - well after midnight - on 23 August with the legions , leaving the cavalry to march to their ships , embark , and join him as soon as possible . In light of later events , this was either a tactical mistake or ( along with the fact that the legions came over without baggage or heavy siege gear ) confirms the invasion was not intended for complete conquest . Landing . Caesar initially tried to land at Dubris ( Dover ) , whose natural harbour had presumably been identified by Volusenus as a suitable landing place . However , when he came in sight of shore , the massed forces of the Britons gathered on the overlooking hills and cliffs dissuaded him from landing there , since the cliffs were so close to the shore that javelins could be thrown down from them onto anyone landing there . After waiting there at anchor " until the ninth hour " ( about 3pm ) waiting for his supply ships from the second port to come up and meanwhile convening a council of war , he ordered his subordinates to act on their own initiative and then sailed the fleet about seven miles along the coast to an open beach . In the absence of archaeological evidence at the landing point , this beach was most probably at Walmer , which is the right distance up the coast from the White Cliffs . It was thought in the 19th century to be near Deal Castle , a house there named SPQR , but is now thought to be half a mile further south , where it is now marked by a concrete memorial . Having been tracked all the way along the coast by the British cavalry and chariots , the landing was opposed . To make matters worse , the Roman ships were too large to go close inshore and the troops had to disembark in deep water , all the while attacked by the enemy from the shallows . The troops were reluctant , but according to Caesar ' s account were led by the " aquilifer " ( standard bearer ) of the 10th legion who jumped in first as an example , shouting : The British were eventually driven back with " catapultae " and slings fired from the warships into the exposed flank of their formation and the Romans managed to land and drive them off . The cavalry , delayed by adverse winds , still had not arrived , so the Britons could not be pursued and finished off , and Caesar could not enjoy what he calls , in his usual self - promoting style , his " accustomed success " . Beach - head . The Romans established a camp of which no archaeological trace has been found , received ambassadors and had Commius , who had been arrested as soon as he had arrived in Britain , returned to him . Caesar claims he was negotiating from a position of strength and that the British leaders , blaming their attacks on him on the common people , were in only four days awed into giving hostages , some immediately , some as soon as they could be brought from inland , and disbanding their army . However , after his cavalry had come within sight of the beachhead but then been scattered and turned back to Gaul by storms , and with food running short , Caesar , a native of the non - tidal Mediterranean , was taken by surprise by the British tides . At high tide , his beached warships filled with water , and his transports , riding at anchor , were driven against each other . Some ships were wrecked , and many others were rendered unseaworthy by the loss of rigging or other vital equipment , threatening the return journey . Realising this and hoping to keep Caesar in Britain over the winter and thus starve him into submission , the Britons renewed the attack , ambushing one of the legions as it foraged near the Roman camp . The foraging party was relieved by the remainder of the Roman force and the Britons were again driven off , only to regroup after several days of storms with a larger force to attack the Roman camp . This attack was driven off fully , in a bloody rout , with improvised cavalry that Commius had gathered from pro - Roman Britons and a Roman scorched earth policy . Conclusion . The British once again sent ambassadors and Caesar , although he doubled the number of hostages , realised he could not hold out any longer and dare not risk a stormy winter crossing , Caesar had set out late in the campaigning season and the winter solstice was approaching , and so allowed them to be delivered to him in Gaul , to which he returned with as many of the ships as could be repaired with flotsam from the wrecked ships . Even then , only two tribes felt sufficiently threatened by Caesar to actually send the hostages , and two of his transports were separated from the main body and made landfall elsewhere . Success and motivation . In short , the campaign had not been a success . If it had been intended as a full - scale campaign , invasion or occupation , it had failed , and even if it is seen as a reconnaissance - in - force or a show of strength to deter further British aid to the Gauls , it had fallen short . Nonetheless , going to Britain at all carried such kudos for a Roman that the Senate decreed a " supplicatio " ( thanksgiving ) of twenty days when they received Caesar ' s report . Caesar ' s pretext for the invasion was that " in almost all the wars with the Gauls succors had been furnished to our enemy from that country " . This is plausible , although it may also have been a cover for investigating Britain ' s mineral resources and economic potential : afterwards , Cicero refers to the disappointing discovery that there was no gold or silver in the island ; and Suetonius reports that Caesar was said to have gone to Britain in search of pearls . Second invasion ( 54 BC ) . Preparation . A second invasion was planned in the winter of 55 - 54 for the summer of 54 BC . Cicero wrote letters to his friend Gaius Trebatius Testa and his brother Quintus , both of whom were serving in Caesar ' s army , expressing his excitement at the prospect . He urged Trebatius to capture him a war chariot , and asked Quintus to write him a description of the island . Trebatius , as it turned out , did not go to Britain , but Quintus did , and wrote him several letters from there - as did Caesar himself . Determined not to make the same mistakes as the previous year , Caesar gathered a larger force than on his previous expedition with five legions as opposed to two , plus two - thousand cavalry , carried in ships which he designed , with experience of Venetic shipbuilding technology , to be more suitable to a beach landing than those used in 55 BC being broader and lower for easier beaching . This time he names Portus Itius as the departure point . Crossing and landing . Labienus was left at Portus Itius to oversee regular food transports from there to the British beachhead . The military ships were joined by a flotilla of trading ships captained by Romans and provincials from across the empire , and local Gauls , hoping to cash in on the trading opportunities . It seems more likely that the figure Caesar quotes for the fleet ( 800 ships ) include these traders and the troop - transports , rather than the troop - transports alone . Caesar landed at the place he had identified as the best landing - place the previous year . The Britons did not oppose the landing , apparently , as Caesar states , intimidated by the size of the fleet , but equally this may have been a strategic ploy to give them time to gather their forces , or may reflect their lack of concern . Kent campaign . Upon landing , Caesar left Quintus Atrius in charge of the beach - head and made an immediate night march twelve miles inland , where he encountered the British forces at a river crossing , probably somewhere on the River Stour . The Britons attacked but were repulsed , and attempted to regroup at a fortified place in the forests , possibly the hillfort at Bigbury Wood , Kent , but were again defeated and scattered . As it was late in the day and Caesar was unsure of the territory , he called off the pursuit and made camp . However , the next morning , as he prepared to advance further , Caesar received word from Atrius that , once again , his ships at anchor had been dashed against each other in a storm and suffered considerable damage . About forty , he says , were lost . The Romans were unused to Atlantic and Channel tides and storms , but nevertheless , considering the damage he had sustained the previous year , this was poor planning on Caesar ' s part . However , Caesar may have exaggerated the number of ships wrecked to magnify his own achievement in rescuing the situation . He returned to the coast , recalling the legions that had gone ahead , and immediately set about repairing his fleet . His men worked day and night for approximately ten days , beaching and repairing the ships , and building a fortified camp around them . Word was sent to Labienus to send more ships . Caesar was on the coast on 1 September , from where he wrote a letter to Cicero . News must have reached him at this point of the death of his daughter Julia , as Cicero refrained from replying " on account of his mourning " . March Inland . Caesar then returned to the Stour crossing and found the Britons had massed their forces there . Cassivellaunus , a warlord from north of the Thames , had previously been at war with most of the British tribes . He had recently overthrown the king of the powerful Trinovantes and forced his son , Mandubracius , into exile , but now the Britons had appointed him to lead their combined forces . After several indecisive skirmishes , during which a Roman tribune , Quintus Laberius Durus , was killed , the Britons attacked a foraging party of three legions under Gaius Trebonius , but were repulsed and routed by the pursuing Roman cavalry . Cassivellaunus realised he could not defeat Caesar in a pitched battle . Disbanding the majority of his force and relying on the mobility of his 4 , 000 chariots and superior knowledge of the terrain , he used guerrilla tactics to slow the Roman advance . By the time Caesar reached the Thames , the one fordable place available to him had been fortified with sharpened stakes , both on the shore and under the water , and the far bank was defended . Second Century sources state that Caesar used a large war elephant , which was equipped with armour and carried archers and slingers in its tower , to put the defenders to flight . When this unknown creature entered the river , the Britons and their horses fled and the Roman army crossed over and entered Cassivellaunus ' territory . The Trinovantes , whom Caesar describes as the most powerful tribe in the region , and who had recently suffered at Cassivellaunus ' hands , sent ambassadors , promising him aid and provisions . Mandubracius , who had accompanied Caesar , was restored as their king , and the Trinovantes provided grain and hostages . Five further tribes , the Cenimagni , Segontiaci , Ancalites , Bibroci and Cassi , surrendered to Caesar , and revealed to him the location of Cassivellaunus ' stronghold , possibly the hill fort at Wheathampstead , which he proceeded to put under siege . Cassivellaunus sent word to his allies in Kent , Cingetorix , Carvilius , Taximagulus and Segovax , described as the " four kings of Cantium " , to stage a diversionary attack on the Roman beach - head to draw Caesar off , but this attack failed , and Cassivellaunus sent ambassadors to negotiate a surrender . Caesar was eager to return to Gaul for the winter due to growing unrest there , and an agreement was mediated by Commius . Cassivellaunus gave hostages , agreed an annual tribute , and undertook not to make war against Mandubracius or the Trinovantes . Caesar wrote to Cicero on 26 September , confirming the result of the campaign , with hostages but no booty taken , and that his army was about to return to Gaul . He then left , leaving not a single Roman soldier in Britain to enforce his settlement . Whether the tribute was ever paid is unknown . Aftermath . Commius , Caesar ' s Atrebatian ally , later switched sides , fighting in Vercingetorix ' s rebellion . After a number of unsuccessful engagements with Caesar ' s forces , he cut his losses and fled to Britain . Sextus Julius Frontinus , in his " Strategemata " , describes how Commius and his followers , with Caesar in pursuit , boarded their ships . Although the tide was out and the ships still beached , Commius ordered the sails raised . Caesar , still some distance away , assumed the ships were afloat and called off the pursuit . Archaeologist John Creighton believes that this anecdote was a legend , and that Commius was sent to Britain as a friendly king as part of his truce with Mark Antony . Commius established a dynasty in the Hampshire area , known from coins of Gallo - Belgic type . Verica , the king whose exile prompted Claudius ' s conquest of AD 43 , styled himself a son of Commius . Discoveries about Britain . As well as noting elements of British warfare , particularly the use of chariots , which were unfamiliar to his Roman audience , Caesar also aimed to impress them by making further geographical , meteorological and ethnographic investigations of Britain . He probably gained these by enquiry and hearsay rather than direct experience , as he did not penetrate that far into the interior , and most historians would be wary of applying them beyond the tribes with whom he came into direct contact . Geographical and meteorological . Caesar ' s first - hand discoveries were limited to east Kent and the Thames Valley , but he was able to provide a description of the island ' s geography and meteorology . Though his measurements are not wholly accurate , and may owe something to Pytheas , his general conclusions even now hold water : No information about harbours or other landing - places was available to the Romans before Caesar ' s expeditions , so Caesar was able to make discoveries of benefit to Roman military and trading interests . Volusenus ' s reconnaissance voyage before the first expedition apparently identified the natural harbour at Dubris ( Dover ) , although Caesar was prevented from landing there and forced to land on an open beach , as he did again the following year , perhaps because Dover was too small for his much larger forces . The great natural harbours further up the coast at Rutupiae ( Richborough ) , which were used by Claudius for his invasion 100 years later , were not used on either occasion . Caesar may have been unaware of them , may have chosen not to use them , or they may not have existed in a form suitable for sheltering and landing such a large force at that time . Present knowledge of the period geomorphology of the Wantsum Channel that created that haven is limited . By Claudius ' time Roman knowledge of the island would have been considerably increased by a century of trade and diplomacy , and four abortive invasion attempts . However , it is likely that the intelligence gathered in 55 and 54 BC would have been retained in the now - lost state records in Rome , and been used by Claudius in the planning of his landings . Ethnography . The Britons are defined as typical barbarians , with polygamy and other exotic social habits , similar in many ways to the Gauls , yet as brave adversaries whose crushing can bring glory to a Roman : Military . In addition to infantry and cavalry , the Britons employed chariots , a novelty to the Romans , in warfare . Caesar describes their use as follows : Technology . During the civil war , Caesar made use of a kind of boat he had seen used in Britain , similar to the Irish currach or Welsh coracle . He describes them thus : Economic resources . Caesar not only investigates this for the sake of it , but also to justify Britain as a rich source of tribute and trade : This reference to the ' midland ' is inaccurate as tin production and trade occurred in the southwest of England , in Cornwall and Devon , and was what drew Pytheas and other traders . However , Caesar only penetrated to Essex and so , receiving reports of the trade whilst there , it would have been easy to perceive the trade as coming from the interior . Outcome . Caesar made no conquests in Britain , but his enthroning of Mandubracius marked the beginnings of a system of client kingdoms there , thus bringing the island into Rome ' s sphere of political influence . Diplomatic and trading links developed further over the next century , opening up the possibility of permanent conquest , which was finally taken up by Claudius in AD 43 . In the words of Tacitus :