The collapse of Roman Britain: what happened, plus 9 places which tell us more

For Ken Dark, director of the University of Reading’s Research Centre for Late Antique and Byzantine Studies, what happened at the end of Roman Britain is probably the biggest unanswered question in British history during the first millennium AD. “The trouble, “he says, “is that the debate is to say the least very sophisticated and subtle”.

In AD 410, after almost four centuries of Roman rule in Britain, the embattled Roman emperor Honorius seems to have issued a declaration that the Britons needed to look to their own defence. What happened next is one of the greatest enigmas in British history and archaeology. Did Roman ways of life stop suddenly and completely, did they carry on, or did they morph into something new?

AD 410 itself may be a red herring. Though the letter from Honorius does exist, some historians dispute whether it actually refers to Britain (part of Italy is another option). Regardless of the validity of the declaration, the end of the Roman period cannot be confined to a single year. “There wasn’t one day on which ‘the Romans’ said ‘we’ll up and go’ and the legions marched out, not least because the Romans weren’t an ethnically defined group,” argues Dark. “Most of them would be descendants of the local Britons who’d inhabited Britain for centuries before the Roman conquest but they would have also included a substantial multicultural population drawn from all over the Roman empire. Before, say, 400, most of that population would probably have considered itself to be Roman, in the sense of being Roman citizens.”

Whatever actually happened in 410, there was a move in the fifth century from a Roman to a post-Roman society across Europe, as imperial influence waned. Britain was part of that trend, and it may have changed in line with developments that were happening in other former imperial provinces in western Europe. Two main trends were the increasing spread of Christianity and the incorporation of ‘barbarian’ – that is, non-Roman – cultural attributes. These changes were widespread in Roman society across the empire, but the fifth century also saw the movement of ‘barbarian’ peoples into Roman territory in far greater numbers – and frequently as rulers or raiders rather than refugees or Roman soldiers.

In Britain, we usually call these fifth-century (and later) Germanic migrants ‘the Anglo-Saxons’ though neither they nor anyone else referred to them by that name in the fifth century. Nor is it known whether the Anglo-Saxons initially came as invaders or settlers, in large numbers or small groups, or to live among or to lord over the Britons. Ken Dark’s view is that they did come in large numbers, but what they did when they arrived is complicated:

“I believe that there was mass migration across the North Sea by Germanic peoples and that they settled in substantial parts of eastern Britain, most notably East Anglia. In those places they brought their own cultures very substantially intact, but there were other areas, even in the east of Britain, where Germanic and British communities lived side-by-side or together and where their cultural practices and values co-existed or merged.” To the west and north of these ‘Anglo-Saxon’ areas, British kings ruled over large independent kingdoms in the fifth and sixth centuries, with populations wholly or largely descended from those of Roman Britain.

The latter point is crucial. One of the big advances in the study of the period in the last few decades has been the framing of the debate in terms of the existing occupants and away from the previous heavy focus on the incoming Anglo-Saxons. At least until the end of the sixth century the Britons controlled the majority of what had been Roman Britain, not the Anglo-Saxons, and so the need to study the Britons for themselves rather than as a footnote to the Anglo-Saxons has been widely recognised.

Indeed, many specialists now term these centuries of British history ‘Late Antiquity’ – a term widely used in relation to the fifth and sixth-century history of the rest of what had been the Roman empire – rather than the ‘Early Anglo-Saxon period’. This shift in focus, closely associated with Dark’s work on the period, has enabled historians and archaeologists to look more closely at what happened to the remaining Britons, and to identify that some elements of Roman culture did cross over to their post-Roman world.

Gradually, however, the Roman influence waned and in the seventh century we moved into a new world where Anglo-Saxon and British kingdoms jostled for power across a land starting to forget its Roman past.

9 places associated with the collapse of Roman Britain

Where late Roman Britain was to be defended

How were the people of late Roman Britain planning to defend themselves against the threat of barbarian raiders? Go to Portchester and you can see precisely what they had in mind as here is preserved a fine example of the coastal defences of Roman Britain. Though it’s often characterised as a fort of the Saxon Shore (a military command of the Late Roman empire), it may actually have been built in the third century, before that command was established.

It offers an interesting insight into the way in which Roman imperial thinking about defence had changed by the late empire. One of the symbols of that change is the massive, almost castle-like character of late Roman fortifications, which you see very well at Portchester. It’s the only Roman stronghold in Britain whose walls still stand almost complete to their 6m height. It’s had a long life since Roman days, being the site successively of a Norman keep, a 14th-century palace, an embarkation point for the Agincourt campaign and a home for Napoleonic prisoners of war. Despite that it remains a very visible signal of the defensive strategy of the late Roman Britons.

Where the arrival of Christianity is clear to see

This is a substantial late Roman villa site and the surviving fabric makes this a great place to go to consider the nature of villa life at the end of Roman Britain. The villa had been introduced as a settlement type into Britain at the start of the Roman period, and indeed Lullingstone was begun about AD 100. But most known Roman villas in Britain are actually late Roman in date. The great period of flourishing Roman villas in Britain was the fourth century, when large parts of the British landscape was divided up into estates that were centred around them.

Lullingstone is a good example of one of these late-Roman villas. They were often quite modest but they included some that were elaborately decorated and architecturally sophisticated. Lullingstone was towards the top of the range but was not a palatial example (for that, Chedworth in Gloucestershire is worth a visit).

Villas were in part built for showing off. But they also often had a religious element, firstly with links to pagan temples and then perhaps as centres of rural Christianity. The spread of Christianity in the late Roman and post-Roman period is a key part of the story of the end of Roman Britain. Lullingstone’s house-church (a room within an otherwise secular building devoted specifically to Christian observance) shows that Christianity had certainly reached this villa. House churches are hard to spot archaeologically but we know of Lullingstone because it had a splendid series of wall paintings with Christian symbols. The paintings are now in the British Museum but copies can be seen at Lullingstone, along with the layout of the villa.

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Where frontier life carried on, in some form at least

We don’t know exactly what was happening on Hadrian’s Wall in the late Roman period. It was intensively used and still served as some sort of frontier, perhaps for taxation, symbolic and military purposes. To the north of the wall were Britons who were in many ways similar to the Britons south of it, but some of them at least were intent on disrupting life in Roman territory.

You can see a fort, turret and milecastle at Birdoswald, plus the longest unbroken stretch of wall nearby to the east. However, most interesting in terms of the end of Roman Britain is the fact that a large timber hall, now marked out with posts, has been found here, perhaps dating to the fifth century. Does this represent continuous use from Roman to post-Roman periods, or later re-use – and if so by whom? It could have been the case that the Roman period communities at the wall stayed on into the fifth century and that the forts had an ongoing military role, or they might have been abandoned for a while and then refortified by whatever new political powers stepped into the vacuum.

The site’s defensive possibilities were recognised long after the Romans left, with a medieval fortified tower and then an Elizabethan Bastle House being built.

Where the Anglo-Saxons settled

This reconstructed Anglo-Saxon village is positioned on an original settlement site of the period and is an excellent place to go for an introduction to the life of these newcomers from the continent.

It’s a good venue to think about how different the world the Anglo-Saxons were living in was to Roman Britain, as these sort of farming settlements replaced the Roman administrative set-up in the fifth and sixth centuries in eastern Britain. There are numerous Anglo-Saxon type buildings here, constructed in different ways as experimental archaeology projects, based on the data from the excavations carried out here in the 1960s and 70s.

Where Christianity lived on in post-Roman Britain

After the third-century martyrdom of Alban (who was condemned to death for sheltering a Christian), the Roman town of Verulamium became a centre for Christian activity, and there’s literary evidence to suggest that it retained that role through the fifth and sixth centuries. It’s mentioned in the fifth-century Life of St Germanus as a major Christian shrine visited by Germanus as he progressed around eastern Britain in AD 429 trying to fight off the advances of the Pelagian heresy (which essentially posited the belief that people can be good of their own account and thereby implied the denial of original sin). In the mid-sixth century, the British writer Gildas laments that he can’t get to the famous pilgrimage shrine of St Alban because the Anglo-Saxons are in the way. Move forward to the early eighth century and Bede writes about St Albans being a major Christian shrine that has remained in use since Roman times.

The archaeological evidence suggests that there was something going on here in the fifth and sixth centuries, but exactly what is hard to characterise. There’s nothing visibly fifth-century in the fabric of the current cathedral, but the Verulamium Museum gives an overview of life in the Roman city, and you can still see the Roman walls, hypocaust and theatre there.

Where Roman urbanism carried on

This Roman city has been a tourist destination for over 150 years. But it was only as a result of the excavations in the 1960s and 1970s that archaeologists began to truly appreciate the grand scale on which Wroxeter was rebuilt in the fifth and possibly sixth centuries. It’s hard to say when the city finally went out of use but it certainly appears to have had a long life after the end of Roman Britain. This is evidenced by the fact that timber and wattle and daub buildings were built, and then rebuilt perhaps more than once, across a large part of the city centre.

What’s interesting is that these buildings share many affinities with classical Roman architecture, and so in design, layout and size, they are essentially Roman buildings but built of wood not stone. The material culture associated with them is identical to the later fourth century, so we have the latest Roman material culture associated with buildings occupied into the fifth century. It would seem at Wroxeter that there were people attempting to keep the Roman way of life going. If you pay a visit, the great wall that divided the second-century municipal baths from the exercise hall is a reminder of what Roman Britain looked like at its height.

Where the British elite made a show of their power

Not all Britons attempted to carry on urban life like the inhabitants of Wroxeter. Others opted to reoccupy and refortify Iron Age (pre-Roman) hill-forts. The Britons in the immediately post-Roman period replaced Roman local government with kings, and these re-used hill-forts may have been the kings’ royal centres, as they were often associated with the consumption of foreign luxury goods. Cadbury Castle is an excellent example of such a place, where there was clearly some high-status activity going on – as a considerable amount of pottery and glass, imported from the Mediterranean and Gaul, has been found within its huge earthen banks. The ramparts are all that remain for the visitor to see today at this fine hill-fort, which incidentally is happily set in a pleasant corner of rural Somerset.

Where the new kings continued old ways

There was something very significant happening on the north Cornish coast in the fifth and sixth centuries. Archaeologists have found evidence for over 150 buildings at Tintagel, bearing decidedly Roman characteristics such as rectangular layouts and multiple rooms. They were enclosed within a hefty bank and ditch cutting off the landward approach but with access to a natural harbour below. And that harbour was probably a very busy place because an enormous amount of imported Byzantine pottery, amphorae and glass has been discovered in excavations on this site. This all suggests that the settlement at Tintagel, which was established after the end of the Roman period in the fifth century, was in many respects more Roman in its architecture, plan and finds than any other site known in Cornwall.

The recent discovery of a Latin inscription at Tintagel adds weight to the evidence that Roman influence continued to spread in Britain after AD 410. It’s thought that Tintagel was probably a royal site of the British kingdom of Dumnonia, which seems to have encompassed most of England’s south-west peninsula at this time.

Despite their historical importance, the fifth and sixth century remains are rather overshadowed today by the ruins of the 13th-century castle and of course by the pervading Arthurian associations of the place. The coastline is worth a visit in any case.

Where the Latin language lingered

Far from dying out after the end of the Roman period, the language that the Romans imported seems to have lived and indeed spread, at least within the confines of Latin memorial inscriptions. Such things have been found widely from Cornwall through Wales and western Britain right up to the Lake District and into the British kingdoms in southern Scotland. They are probably tombstones, and many have formulaic inscriptions that say “so and so, son of so and so lies here”. The National Museum Cardiff has a collection of these stones, which are easily accessible, so it’s worth a visit to see how Latin continued to be used even after the Romans themselves had gone.

Where British resistance lived on

This imposing two-pronged rocky knoll overlooking the river Conwy was probably the leading royal site of the British kingdom of Gwynedd, which was, roughly speaking, the north-west of Wales, including Anglesey.

Gwynedd was important from at least the sixth century and formed a focus of resistance against the eventual spread of Anglo-Saxon political control as they developed more centralised kingdoms. The last major British victory against the Anglo-Saxons in the 630s was won by one of the kings of Gwynedd. In fact, the Britons of Gwynedd were never conquered by the Anglo-Saxons as such. It was not until long after the formation of the kingdom of England that the English kings took control here. Thus when, in 1282, the area fell to English rule, it was the last part of the western Roman empire to be lost to the political control of people descended from those who had at one time lived within that empire. There isn’t anything of the sixth-century occupation to see at the site today, but evidence of later castles built on the site does survive.

Words by Dave Musgrove. Historical advisor: Ken Dark, University of Reading. This feature was first published in the February 2010 issue of BBC History Magazine.

This article was first published in the March 2010 issue of BBC History Magazine