Conquest and Context

Professor Mark Hassall discusses the reasons for the Roman invasions of Britain by Caesar and Claudius, the settlement of the province of Britannia under Claudius' first governor, Aulus Plautius, where the legions were based, the question of the frontier and the creation of the three client kingdoms.

The purpose of the original version of this paper was to put the Conquest of 43 - wherever the Romans landed - in its context, and this remains the aim of the present contribution. In 'Prelude' I shall take the story back almost a century before the time of Claudius, to Caesar. I shall first discuss the reasons for Caesar's invasion and examine Rome's subsequent relations with Britain down to the eve of the Claudian invasion. I shall then look at the period between the invasions from a British perspective, before turning to the reasons for the invasion of Claudius in AD 43 . In 'Aftermath' I shall look at the first settlement of the province of Britannia under Claudius' first governor, Aulus Plautius, where the legions were based, the question of the frontier, and the creation of the three 'client kingdoms'.

Prelude: The Roman Perspective
Before Britain came Gaul. Caesar's campaigns in Gaul had met with remarkable success, but why did he invade 'Long Haired' or 'Trowsered' Gaul in the first place? He says himself that it was because the proposed migration westwards of the Helvetii threatened the security of Gallia Narbonensis. Rubbish. He invaded Gaul because he had a burning ambition and already had his eyes set on greater things. Caesar wanted to train an army that would be loyal to him through thick and thin, and to amass a fortune in slaves and gold to finance his political ambition. He was successful - almost too successful. By 56 BC it looked as if all Gaul was thoroughly conquered. His enemies and rivals, while congratulating him, were in danger of demanding the return to Rome of some of his precious legions. A new theatre for operations was necessary and the nearest available was Britain. It may be, as Caesar claimed, that Gallic dissidents fled to Britain and that the Britons sent help to their cousins in Gaul, but I believe that the 'military explanation' is not the right one. The invasions were carried out partly for political reasons - to forestall his enemies from asking for the surrender of his legions (this was the C E Stevens explanation) and, quite simply, to get more loot. The invasion in 55 BC was small in scale: legally Caesar should not have been operating outside his (extended) province, and he had to test the political waters at Rome. In the event there was no problem; the expedition 'beyond the Ocean' turned out to be an unexpected propaganda coup, and he was free to return to the island the next year. But there was no gold, as Quintus Tullius ruefully wrote back to his brother, the orator Marcus Tullius Cicero. And the next year the great Gallic revolt broke out and a return was impossible. As a footnote, it should be pointed out that Quintus was not entirely accurate: there was gold, some gold anyway, and the magnificent gold torcs found at Snettisham may have been buried at the time of Caesar's invasions.

A lot had happened between the second invasion of Caesar in 54 BC and the Battle of Actium in 31 BC. There had been three civil wars: Caesar v Pompey, the Caesarians v the Pompeians and one Caesarian faction under Antony against the other under Caesar's great nephew and adopted son, Octavian. Octavian won and became the first emperor of Rome. There were at least three occasions, 34, 27 and 26 BC, when contemporaries thought that Augustus would take up the Caesarian legacy in Britain. He didn't. Why? Augustus and his generals, which included his son-in-law, Agrippa, and his two step-sons, Tiberius and Drusus, were too busy in other areas consolidating the territory that Rome held, in Spain, in the Alps unconquered despite the incorporation of Gaul into the empire, and in the Balkans. In Germany, the Romans advanced the frontier beyond the Rhine as far as the Elbe, which seemed like a suitable stopping place - a temporary frontier before undertaking further expansion. The occupation of Germany came to a disastrous end in AD 9 with destruction of the Roman general Varus and his three legions at the hands of Arminius in the Teutoburg forest. From AD 9 to about AD 40, despite the creation of two new legions, XV and XXII Primigenia, under the mad emperor Gaius Caligula, there was no question of invading Britain, or anywhere else; there simply weren't sufficient troops.

Meanwhile, there was a lucrative trade between Britain and the continent. The Roman Empire was in effect a huge common market, and though there were some duties payable on goods crossing internal frontiers, they were insignificant. There were however much heavier duties levied on goods crossing beyond the Imperial boundaries. And the Romans cashed in on traffic between Britain and Gaul - as Strabo, the Augustan geographer, makes amply clear. The goods traded were luxury items from the Roman side and raw materials from the British, and some of them are listed by Strabo. Britain exported grain along with cattle, gold, silver and iron, hides, slaves, and hunting dogs. Britain imported, from the rest of the Roman Empire, trinkets, and luxury goods, including wine, not mentioned by Strabo, but archaeologically the best attested by finds of amphorae in the graves of British chieftains. The trade would have been carried by substantial merchant ships with leather sails, like the one shown on a rare coin issue of Cunobelin.

Prelude: The British Perspective
What about Britain? The period of almost a century between the second invasion of Caesar in 54 BC and the invasion of Claudius in AD 43 can be categorised as 'proto-historic'. We have not only the evidence of archaeology, but there are the stray references of classical authors and even indigenous evidence in the form of the inscribed coinage of the tribes of southern Britain. One tribal ruler who struck coins was Commius. This man was a chieftain of the Gallic Atrebates (whose name survives in that of the French town of Arras). He had been a friend of Caesar, as Caesar himself tells us, and even acted as a go-between between him and the tribes in Britain in 55 and 54 BC. But at the time of the great Gallic revolt under Vercingetorix his patriotism had outweighed the bonds of friendship, and he had become one of the rebel leaders. After the surrender of Vercingetorix, Commius had continued to lead resistance to Rome until he had finally decided to flee to Britain where part of the Atrebates were settled. The distribution of findspots of hoards of coins struck by Commius and his three sons, Tincomarus, Epillus and Verica, shows the area where their 'writ ran', basically from the Thames through Hampshire and Sussex. It stands in contrast to the distribution of the finds of hoards of coins of Cunobelin and his brother Epaticcus. These men were the rulers of the Catuvellauni and tribes subject to them and their coins are found basically north of the Thames with a scattering
of finds south of the river. Tincomarus is not only known from the inscribed British coinage, he appears as a suppliant in Rome on the so-called Res Gestae ('The Achievements') of the deified Augustus as preserved on the great inscription at Ankara. Why? He had probably been ousted by his brother Epillus; at any rate he was succeeded by him. The same fate befell Verica - if, as seems likely, he is Dio's Berikos - but this time it was probably the Catuvellauni advancing from the north across the Thames who were responsible for his exile.

Who were the Catuvellauni and who were their leaders? An obscure people with a similar name is attested around Chalons in north-eastern Gaul, and, like the Atrebates, it is likely that part of the tribe migrated at some time from the Belgic area of Gaul to south-eastern Britain. Here their first certain leader was Tasciovanus (who may or may not be the son of Caesar's old opponent Cassivellaunus). He minted at Verulamium (St Albans), but his son, Cunobelinus, took over the neighbouring tribal state of the Trinovantes and minted coins at Colchester, the Celtic Camulodunum, the Fort of Camulos, the Celtic war god. Tasciovanus' brother Epaticcus and son Caratacus took over the Atrebatic capital at Calleva (Silchester) - at least they minted coins there. Verica, the third of Commius' sons (unless he was a daughter, as some historians claim!), would appear to have fallen back to Chichester (whose name, Noviomagus, means the New Market). It was protected to the north by the Chichester dykes, but his defenses were breached and Verica was driven into exile. Dio records how Berikos/Verica fled, a suppliant, to Claudius. Before coming on to Verica, however, I should mention the other two sons of Cunobelin, Togodumnus and Adminius. Togodumnus along with Caratacus led the resistance to Claudius in AD 43. Adminius almost certainly is the man who fled to Claudius' predecessor, Gaius Caligula, in AD 41.

The Ostensible Reasons for the Invasion of Britain by Claudius
Our ancient sources give two reasons for the invasion. First, Dio says that Claudius wanted to reinstall Berikos (= Verica). Secondly, Suetonius, the Imperial biographer, says that Claudius, the most unmilitary of men, wanted Glory. The two reasons are not incompatible. If Claudius did want Glory, then the reinstallation of Verica would provide a reasonable casus belli. And it is quite certain that Claudius played the 'Crossing the Ocean' card for all that it was worth: did not the Senate vote him two triumphal arches, one in Rome and one at Boulogne since it was from here that he had crossed over to England? Both have long since disappeared but aurei of Claudius show a stylised representation of the Rome arch and part of the inscription from it survives. On this the emperor is described as the first to subdue the tribes beyond the Ocean to the power of the Roman people, a claim that by implication dismisses Caesar's expeditions as mere military adventures without permanent results. Dio records the name of one of these tribes - the Bodunni. This must be a mistake for the Dobunni of the Gloucestershire area. One of their rulers was called Boduocos we know from their inscribed coinage, so perhaps Dio got confused in his note taking! A relief from the Sebasteion at Aphrodisias, shows Claudius in a state of heroic nudity about to despatch a female figure, the personification of Britannia. Another find, a cameo in the Kunsthistorisches Museum in Vienna, shows Claudius armed with a thunderbolt and a bearded barbarian prisoner at his feet. It finds its perfect counterpart in a poem celebrating Claudius' conquest of Britain in the Latin Anthology, 'thy thunderbolt, great Caesar, now strikes down/the land where Roman triumphs were unknown'. Then there were the games that were celebrated, not to mention the durba when Caratacus was paraded in Rome before the emperor and his consort ten years later. Finally, one might mention Claudius' speech on admitting Gauls to the Roman Senate (its text preserved on the bronze tablet from Lyon) where the emperor gratuitously drags in a reference to this recent expedition to Britain. Claudius - this was your finest hour!

The Possible Main Reason
But there was surely at least one other reason, though it isn't mentioned in any of the sources. Gaius Caligula had raised two new legions for a projected invasion of Germany. That had fallen through because, if we can believe Suetonius, the emperor's attention got diverted to Britain by the arrival of the exiled Adminius. This too ended in farce when the emperor ordered his soldiers to pick up sea shells, 'the spoils of the ocean', and the one concrete result of the episode was the erection of a lighthouse overlooking the Roman naval base at Boulogne. There were now two new legions on the Rhine. Already under Tiberius there was a huge imbalance in the distribution of the legions - eight legions out of a total of 25. The reason for this was either fear in the aftermath of the Varus debacle or a statement of (aggressive) intent in Rome's dealings with Germany, or a mixture of both. With the creation of Gaius' two new legions, XV and XXII Primigenia, the imbalance obviously increased out of all proportion. Something would have to be done.

However, there was more to it than just shuffling round a few legions to get a more even spread around the frontiers. Claudius had been raised to the purple by the praetorians in Rome. Quite apart from the service rivalry between the two branches of the army - praetorians and legionaries - there were many who hankered for the good old days of the Republic. When Claudius came to Britain he was attended by a number of high ranking senators as comites ('companions'). Some, like Plautius Aelianus, who was related to the commander Aulus Plautius, may have been friends, but in the case of many others it was because Claudius simply dared not leave them behind... Claudius' position was desperate in the extreme. All that was needed was
an ambitious legate of one of the Rhine legions to raise the standard of revolt with the claim that he was restoring the Republic and Claudius was a dead man. It probably wouldn't have been necessary to take the Rhine legions into Italy for the coup to have succeeded, and it nearly happened. The story of the mutiny on the eve of the invasion sounds like farce but it was more deadly than that. The fate of the Empire hung on a knife edge. At a parade Plautius, the senatorial legate, stepped aside to let Narcissus, ex-slave and Imperial emissary, address the troops. The legions were affronted and it was only the Io Saturnalia joke of some wag of a caligatus (private soldier) that defused a tense situation and saved for Claudius his throne.

But what was Claudius actually trying to achieve in Britain? What did he achieve? To throw light on these questions we must look at the immediate post-conquest period.

Aftermath
A glance at a map of Roman Britain shows that remarkable road the Fosse Way stretching from Exeter in the south-west to Lincoln in the north-east. This is Collingwood's famous 'Fosse Frontier'. Along the line, finds of military tombstones show that there were garrisons at places like Bath, where an ala of Vettones was stationed, and Cirencester where we know of two successive units, the ala Indiana (from Gaul) and an ala of Thracians (from Bulgaria). At Cirencester we also know something of the plan of the fort. There were in addition garrison posts in front of the line, at least at Kingsholm, outside Gloucester, on which the road from Cirencester is aligned. This site, at the lowest point on the Severn that could be crossed by a bridge, was of great strategic significance and was later occupied by the first Gloucester legionary fortress. In the early Claudian period there were more Thracians stationed here. We can never hope to have anything like a full picture of the auxiliary dispositions, let alone place particular units in particular forts (there should have been about 50 auxiliary units in total). Even ignoring the question of unit identity, so many fort sites or probable fort sites are known that not all can have been occupied at the same time. There is hope, however, that it may be possible to locate the winter quarters of the four legions which landed in AD 43.

This begs a question: were there four bases? Under Tiberius half the legions were located in double legionary fortresses like Vetera (Xanten), on the Rhine, and in the past scholars have wondered whether in this period some of the legions may have been housed in double legionary fortresses. Sheppard Frere on the other hand has suggested the opposite: that some of the legions, if not a majority, were split up and accommodated in 'half' legionary fortresses. The type site of such a 'vexillation' fortress is Longthorpe, near Lincoln discovered first from the air and subsequently excavated by Frere. This has produced fragments of lorica segmentata (cuirass), thought at one time to have been used exclusively by legionaries (something which, thanks to Val Maxfield, we now know not to have been the case. Even if it were, there may have been just a few legionaries present, as there were in the auxiliary fort at Vindolanda). If Frere were right and Plautius divided his legions into halves and accommodated them in half legionary fortresses then he would be acting in a contrary way to contemporary practice elsewhere in the Empire. But if half legions are out, how do we explain the vexillation fortresses? In my opinion these were the winter quarters of concentrations of auxiliaries - there is epigraphic and literary evidence for army groups of auxiliaries perhaps (loosely) attached to individual legions. Another problem of Frere's interpretation is that there are just too many vexillation fortresses if these were occupied by half legions.

A simpler solution is to assume that the legions were not split up and were housed in full sized fortresses (even in double legionary fortresses?). To the present writer the following scheme on present evidence seems to be the most likely: a fortress for Legion XX at Colchester (where there is both epigraphic and archaeological evidence); a possible double fortress at Leicester for Legions IX and XIV, linked to Colchester by a direct cross-country road; and a fortress for Legion II Augusta at Silchester. Only, it has to be admitted, is the evidence certain at Colchester, where we have not only the fine tombstone of Marcus Favonius Facilis, a centurion in Legion XX, but also another splendid one of the Thracian Longinus. Longinus could have been in the fort known to have existed at Gosbecks, but his unit could also have been based in the legionary fortress itself alongside Legion XX; as at Neuss in Germany, where auxiliaries are known to have been accommodated alongside the legion, there is enough room at Colchester. Leicester remains an enigma: there are military ditches there and its siting on the Fosse Way, and with a direct link with Colchester, would indicate that at the very least there must have been an important auxiliary fort there, but there is no evidence for a legionary fortress, let alone a double legionary fortress! If it were not, then two more legionary fortresses remain to be found, for this the first phase of the Claudian occupation. (Towcester and Alchester? The latter site is currently interpreted by its excavator as a vexillation fortress).

As for Silchester, there is suggestive evidence from below the basilica, where a timber predecessor of the stone structure could have been a timber principia of the hypothetical legionary fortress. Mike Fulford's excavations at Silchester may produce more evidence for the earliest Roman phases. If not Silchester, then Chichester is a possibility and has indeed been suggested by Graham Webster. If Silchester were the first base of Legion II in Britain, when this was evacuated (under Ostorius Scapula?) then the site could have been returned to the Atrebates when Ostorius Scapula, Aulus Plautius' successor, moved troops to the west, and, as Tacitus tells us, created or enlarged the kingdom of Cogidubnus/ Togidubnus by 'the gift of certain civitates'.

To summarise what I believe to have been the situation on the departure of Aulus Plautius: the Fosse Way was of great strategic significance, but was not a frontier as such, certainly not a political frontier. This, the western border of the new province, was formed by the western borders of tribes like the Dobunni and Corieltauvi which, despite having their chef lieu placed on the Fosse (at Cirencester and Leicester), were actually incorporated into the province. The sites of the legionary fortresses we have already discussed. This leaves only the client kingdoms. Two, the Iceni and the Regnum of Verica and his/her successor Togidubnus/Cogidubnus, lay physically within the area occupied, but actually extra regulam provinciae, to use a technical expression, while the third, Brigantia, the kingdom of Cartimandua, lay beyond the frontier of the fledgling province.

Was this the sort of settlement that Claudius intended when he decided, or was pushed, into invading in 43? Perhaps. Or was it simply the pragmatic short-term solution arrived at by his first governor, Plautius, whose acts (along with those of Claudius under whose auspices he was acting) were ratified in advance by the Senate (Dio). If so was total conquest the long-term aim? At all events the settlement was not to last, and Plautius' immediate successor, Ostorius Scapula, was to find a full-scale war on his hands when he entered his province. Caratacus had made his way to the west after his defeat in 43 and was now the focus of resistance. All was not quiet on the western front.