Sub-Roman Britain, also called post-Roman Britain or Dark Age Britain, is the period of Late Antiquity in Great Britain between the end of Roman rule and the founding of Anglo-Saxon kingdoms. The term was originally used to describe archaeological remains found in 5th- and 6th-century AD sites that hinted at the decay of locally made wares from a previous higher standard under the Roman Empire. It is now used to describe the period that began with the recall of Roman troops from Britannia to Gaul by Constantine III in 407 and ended with the Battle of Deorham in 577. This period has attracted a great deal of academic and popular debate, in part because of the lack of written records from the time.
Meaning of terms The period of sub-Roman Britain traditionally covers the history of the parts of Britain that had been under Roman rule from the end of Roman imperial rule, traditionally dated to be in 410, to the arrival of Saint Augustine in 597. The date taken for the end of this period is arbitrary in that the sub-Roman culture continued in northern England until the merger of Rheged (the kingdom of the Brigantes) with Northumbria by dynastic marriage in 633, and longer in the west of Britain, and Cornwall, Cumbria and Wales especially.
The term "post-Roman Britain" is also used for the period; "sub-Roman" and "post-Roman" are terms that apply to the old Roman province of Britannia, i.e. Britain south of the Forth–Clyde line. The history of the area between Hadrian's Wall and the Forth–Clyde line is similar to that of Wales (see Rheged, Bernicia, Gododdin and Strathclyde). North of the line lay a thinly populated area including the kingdoms of the Maeatae (in Angus), Dalriada (in Argyll), and the kingdom whose kaer (castle) near Inverness was visited by Saint Columba. The Romans referred to these peoples collectively as Picti, meaning 'Painted Ones'.
The term "late antiquity", implying wider horizons, is finding more use in the academic community, especially when transformations of classical culture common throughout the post-Roman West are examined. The period may also be considered as part of the early Middle Ages, if continuity with the following periods is stressed. Popular (and some academic) works use a range of more dramatic names for the period: the Dark Ages, the Brythonic Age, the Age of Tyrants, or the Age of Arthur.John Morris, The Age of Arthur (1973) is his title for a popular history of the British Isles from 350 to 650.
Written accounts Little extant written material is available from this period, though a considerable amount from later periods may be relevant. A lot of what is available deals with the first few decades of the 5th century only. The sources can usefully be classified into British and continental, and into contemporary and non-contemporary.
Two primary contemporary British sources exist: the Confessio of Saint Patrick and Gildas' (On the Ruin and Conquest of Britain).Discussion in Ken Dark, Britain and the End of the Roman Empire, (Stroud: Tempus, 2000), pp.32–37 Patrick's Confessio and his Letter to Coroticus reveal aspects of life in Britain, from where he was abducted to Ireland. It is particularly useful in highlighting the state of Christianity at the time. Gildas is the nearest to a source of sub-Roman history, but there are many problems in using it; the document represents British history as he and his audience understood it. Though a few other documents of the period do exist, such as Gildas' letters on monasticism, they are not directly relevant to British history. Gildas' De Excidio is a jeremiad: it is written as a polemic to warn contemporary rulers against sin, demonstrating through historical and biblical examples that bad rulers are always punished by God – in the case of Britain, through the destructive wrath of the Saxon invaders. The historical section of De Excidio is short, and the material in it is clearly selected with Gildas' purpose in mind. There are no absolute dates given, and some of the details, such as those regarding the Hadrian's and Antonine Walls are clearly wrong. Nevertheless, Gildas does provide us with an insight into some of the kingdoms that existed when he was writing, and how an educated monk perceived the situation that had developed between the Anglo-Saxons and the Britons.
More continental contemporary sources mention Britain, although their information is sparse and open to question. The Historia Nova of Byzantine scholar Zosimus notes in passing that western Emperor Honorius, in the throes of Alaric's invasion in 410, sent a rescript to British cities that they must look to their own defence. Some historians have suggested that the reference was instead to Bruttium, but Gildas describes Britain receiving just such a message.Birley, Anthony Richard The Roman Government of Britain OUP Oxford (29 September 2005) pp.461–463 Halsall, Guy Barbarian migrations and the Roman West, 376–568 Cambridge University Press; illustrated edition (20 December 2007) pp.217–218Discussion in Martin Millett, The Romanization of Britain, (Cambridge: Cambridge University Press, 1990) and in Philip Bartholomew 'Fifth-Century Facts' Britannia vol. 13, 1982 p. 260 The Gallic chronicles, Chronica Gallica of 452 and Chronica Gallica of 511, say prematurely that "Britain, abandoned by the Romans, passed into the power of the Saxons" and provide information about Saint Germanus and his visit or visits to Britain, though again this text has received considerable academic deconstruction.Michael Jones and John Casey, 'The Gallic Chronicle Restored: A Chronology for the Anglo-Saxon Invasions and the End of Roman Britain', Britannia 19, (1988), pp.367–398; R.W. Burgess, 'The Dark Ages Return to Fifth-Century Britain: The 'Restored' Gallic Chronicle Exploded', Britannia 21, (1990), pp.185–195 The work of Procopius, another 6th-century Byzantine writer, makes some references to Britain, though the accuracy of these is uncertain.
Numerous later written sources claim to provide accurate accounts of the period. The first to attempt this was the monk Bede, writing in the early 8th century. He based his account of the sub-Roman period in his Historia ecclesiastica gentis Anglorum (written around 731) heavily on Gildas, though he tried to provide dates for the events Gildas describes. It was written from an anti-Briton point of view. Later sources, such as the Historia Brittonum often attributed to Nennius, the Anglo-Saxon Chronicle (again written from a non-Briton point of view, based on West Saxon sources) and the Annales Cambriae, are all heavily shrouded in myth and can only be used with caution as evidence for this period.David Dumville, "Sub-Roman Britain: History and Legend", History 62, (1977), pp.173–192 There are also documents giving Welsh poetry (of Taliesin and Aneirin) and land deeds (Llandaff charters) that appear to date back to the 6th century.
After the Norman Conquest there were many books written that purport to give the history of the sub-Roman period. These have been influenced by the fictionalised account in Geoffrey of Monmouth's Historia Regum Britanniae (History of the Kings of Britain). Therefore, they can only be regarded as showing how the legends grew. Not until modern times have serious studies of the period been undertaken. Later Lives of Celtic saints, although often unreliable, do provide some insights into life in sub-Roman Britain. For example, there is a description of a dilapidated but still occupied Roman villa near Chepstow (probably at Portskewett) included in an account of a visit by Saint Tatheus; and the Roman ruins of Carlisle, as they were in 685, are described in a Life of Saint Cuthbert.
Archaeological evidence
Archaeology provides further evidence for this period, in some cases suggesting that the depopulation of Roman towns and the development of villa and estate organization was already occurring in the 4th century."Town and Country: The End of Roman Britain", World Archaeology 12(1), (June 1980:77–92); Simon T. Loseby, "Power and towns in Late Roman Britain and early Anglo-Saxon England" in Gisela Ripoll and Josep M. Gurt, eds., Sedes regiae (ann. 400–800), (Barcelona, 2000: pp. 319–370 (on-line text ) makes a strong case for the discontinuity of urban life. The 5th and 6th centuries in Britain are marked by a sharp discontinuity in town life, with the exception of a few sites such as Londinium, Eboracum, Canterbury and Wroxeter,Philip Barker's excavation in the Baths Basilica at Wroxeter, (1975) is noted by R. Reece, "Town and country: the end of Roman Britain", World Archaeology, 1980. but the discontinuity in the episcopate also suggests a decline in town life.H.R. Loyn, Anglo-Saxon England and the Norman Conquest, 2nd ed. 1991:15f: "it is altogether unlikely that organized town-life can have survived through the troubles of the fifth and sixth centuries. Gildas lamented the destruction of the twenty-eight cities of Britain, and there is no reason to doubt the essential truth of his statement" (p16). The Roman villa system, represented by some 500 archaeological sites, did not survive either; unlike Gaul, in Britain no villa names survived into the Germanic period. However, at Chedworth, building work continued: a mosaic within Room 28, discovered in 2020, was designed and created in the middle of the 5th century.The 5th Century Chedworth Mosaic: https://archaeologynationaltrustsw.wordpress.com/tag/chedworth-roman-villa/
In the sub-Roman period, building in stone gradually came to an end; buildings were constructed of less durable materials than during the Roman period. However, brooches, pottery, and weapons from this period have survived. The study of burials and cremations, and the grave goods associated with these, has done much to expand the understanding of cultural identities in the period.A.S. Esmonde Cleary, "The Roman to medieval transition" in Britons and Romans: advancing an archaeological agenda. ed. S. James & M. Millett, (York: Council for British Archaeology, 2001) Archaeology has shown some evidence of continuity with Roman education, trade with the Mediterranean, and with Celtic art. Archaeological excavations in south Wales in 2023 sought evidence of an early medieval monastery and school said to have been founded by Saint Illtud in the early 6th century, the forerunner of St Illtyd's Church, Llantwit Major (c.1100).