History Files


Roman Britain

The End of Roman Britain

by Peter Kessler, 30 June 2007



Part 1 Part 2 Part 3 Part 4 Part 5

Part 1: Western decline

The decline of Roman control over Britain was a drawn-out affair which took perhaps a quarter of a century to complete, and it created a twilight period in which Roman civilisation gradually dwindled and died away.

The seeds were sown in the fourth century decline seen throughout the Western Roman Empire, as barbarian tribes continued to make deeper incursions into Gaul, Hispania, and Italy, and then began to settle. The rot had set in, and with it came rebellion, lost territory, and subsequent losses in vitally-needed manpower and resources. The period ended in a mist of obscure references and hazy recollections which were often only written down generations later.

The decline in Britain was a slightly different affair from that in Gaul. Britain was protected from the waves of barbarians crossing the Rhine and the Danube, and only had to put up with the marginally lesser problem of raiding Picts, Irish Scots and Saxons.

'Prince Maximus'

With hindsight, the decline of Roman influence in Britain could be said to have started with the revolt of Magnus Maximus in AD 383 - not that it was seen that way by those living through that time.

The process ended in 409, when the Britons expelled Roman authority from the country, although the repercussions lasted much longer, but the causes seem to have mostly come from overseas; from Gaul and Italy.

In 383 Maximus took advantage of the growing contempt for the failing Roman emperor Gratian by revolting and invading Gaul with a large army. In preparation, he took various steps to preserve the security of his powerbase. He shored up the defences of Wales to protect the west coast from Irish raiders, making sure so that it was as strong as the east coast with its line of Saxon Shore defences. He settled a band of Votadini warriors in North Wales, and legitimised the settlements of Irish Scotti in south-western Wales, setting up the Deisi to act as laeti there under a local British governor.

At the same time as this work was being carried out, some of the Pennine and Welsh forts were abandoned and the Twentieth Legion was withdrawn from Chester - both actions which can easily be ascribed to Maximus.

In fact, his policy of shuffling forces around the island and delivering others with clear cut defensive roles became such a successful policy that the raids on Britain dried up in the late fourth and early fifth centuries. The Irish Dalriata, instead of trying to grab land in Britain, went north beyond the Wall to carve out a successful kingdom on the western edge of Pictland, eventually forming Scotland out of it.

Maximus presumably selected Coel Hen as his replacement for Northern Britain, covering the vital defences of Hadrian's Wall, and 'governing' the semi-friendly Britons between that and the Antonine Wall. Evidence on Coel Hen is extremely murky, and more can be learnt about his role in British history from the actions of his descendants than from him directly.

Maximus is also credited by Geoffrey of Monmouth with setting up the rebellious nephew of Octavius, Conan Meriadoc, as ruler of Armorica, perhaps along the same lines as the British leaders who apparently continued to claim a high kingship in Roman Britain.

There certainly seems to have been the creation of an independent authority in Armorica around this time, as well as an increasing British influence, drawing the region away from Roman central authority in a series of rebellions so that, by 418, they were acknowledged as being almost completely independent of Rome.

The reorganisations by Magnus Maximus and his withdrawal of some army units from Britain almost signals the end of direct Roman rule over the island. There was a central administration, true, and even a mint at London during Maximus' reign, but the island rarely came under direct control from Italy after this point.

As if to underline this, from this date forwards, all of the names claimed as high kings of Britain originate from within the country whereas for the previous three hundred years they had included a large number of Roman emperors. The British perspective on who ruled them had clearly undergone a change.

Pursuing the Purple

Magnus Maximus left Britain in AD 383 in pursuit of his claim to the purple. He made extremely good headway in Gaul, securing Armorica (which now commenced in being a sister-state of Britain's), and then heading towards the south. After defeating Emperor Gratian and forcing Valentinian III out of Rome, Maximus set up his court at Augusta Treverorum (Trier) and by all accounts became a popular emperor.

He took with him all the troops freed up by his reorganisations, and apparently left the island in a fairly good defensive position, despite the loss of good, Roman-trained troops who apparently never returned to Britain. Did this drain on manpower make a difference? If it didn't make a real difference (due to the reorganisations) then it might well have made a perceived difference amongst the barbarians to the north. They could scent an opportunity in the making.

It seems that between 384 to 390 warfare flared up with the Picts again, and according to Gildas (referring to it as the first of his 'Pictish wars'), it lasted 'for many years'.

However, Maximus himself hardly betrayed the signs of someone who had a major battlefront behind him, especially when he launched an attack on Italy in 387 (which, ultimately, was ill-fated, but due only to the better generalship of his opponent), so the situation was probably contained satisfactorily by his deputy in Britain, at least up to this date.

Maximus lost his own war and was executed in 388. Upon his death, the situation in Britain may have worsened. Perhaps the barbarians had learnt of events on the Continent and saw the time was right. They are believed to have attacked south of Hadrian's Wall, although no details are known, and the Britons, overwhelmed, sent a plea for assistance to the emperor.

Roman Trier basilica

The Roman basilica in Trier

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Emperor Theodosius, who had defeated Maximus, waited. The Britons were forced to send assurances of their renewed loyalty to him before he dispatched a legion, probably by 390, to help stop the Pictish attacks. This "legio" may not have been a Roman legion in the traditional sense, but more of a specialist taskforce, something that was becoming more frequent in the Western Empire at this time.

The taskforce must have done its work and ended the immediate threat. Gildas states that rebuilding work took place on the Walls afterwards, with the Britons being instructed on this process, suggesting that the taskforce was not to stay and the Britons must look increasingly to their own defence.

In fact, it seems likely that the legion did become semi-permanent (and there is a proven tendency for armies or imperial comitatenses (in effect, royal guards units), each under a comes, to become localised, acquiring local titles.

Britannia was again isolated from Rome by the revolt of Arbogast and Eugenius in 392 to 394, but this revolt took place entirely on the Continent, in Italy and the Balkans, so the island probably wasn't directly affected. How the Britons saw the situation is anyone's guess, but it may have had implications for their later actions in relation to imperial control over the island.

Fundamental changes to imperial practices

The accession of Honorius and Arcadius in 395 was marked by a basic change in the role of the emperor. It affected the east and west differently, and what happened is of major importance in comprehending what occurred subsequently in the two halves of the empire. Roman emperors after Theodosius were heads of state but no longer held effective power. This now fell into the hands of their chief ministers.

The change was complete in the west, but less so in the east where occasional emperors still took direct command. Perhaps the crucial difference was that in the east the ministers were usually civilians, but in the west they were almost without exception professional soldiers who tended to dominate their emperors.

Due partially to this, and to a series of problems, Honorius' reign was characterised by periods of chaos, and the erosion of the Western Roman Empire and its territories. Successive chief ministers played politics to ensure their own survival, that of the empire, and sometimes that of the emperor himself, but despite the best intentions of the best of them, the empire rarely benefited in the long term. When Honorius died he left an empire on the verge of collapse.

However, while he was still alive there were clearly battles to be fought. In 398, according to the poet Claudian, it appears that Roman forces were able to assert control over the sea approaches to the north-western provinces, and this also included defeating both Saxons and Irish Scotti off the coast of Britain.

It is not clear whether the Picts, also mentioned as being beaten, are included as sea-borne enemies or whether their mention is intended to refer to a purely land-based campaign, which overall has been linked to the second of Gildas' 'Pictish wars'.

However, it seems possible that there was in fact no victory in 398, and the chief minister, or prefect, in the West, Stilicho, who had already been abandoning forts at the beginning of his regency, merely attended to the island's defences before withdrawing more troops, probably the previously settled taskforce, thus further running down the garrison of Britain.

General Stilicho

Did Stilicho ever win a victory against Saxons and Scotti off Britain's coast in AD 398, or was it propaganda?

Again scenting weakness, while Rome was occupied the usurper Gildo in Africa, the barbarians took the opportunity to attack but were thrown off-balance by the unexpected collapse of Gildo's forces in Africa and did not press home their attack.

Finally, though the planned withdrawal was resumed, the warning was heeded and measures were taken to strengthen the defences of Britain.



Text copyright P L Kessler, drawn in part from Peter Salway's Roman Britain (Oxford History Series), with additions. An original feature for the History Files.