Post-Roman Britain

Sub-Roman Britain is a term derived from an archaeological label for the material culture of Great Britain in Late Antiquity, the transition period between the Roman Empire's Crisis of the Third Century around AD 235 (and the subsequent collapse and end of Roman Britain), until the start of the Early Medieval period. The term "Post-Roman Britain" is also used for the period, mainly in non-archaeological contexts.

The term "sub-Roman" was originally used to describe archaeological remains such as potsherds found in sites of the 5th and 6th centuries, and hinted at the decay of locally-made wares from a previous higher standard that had existed under the Roman Empire. It is now more often used to denote this period of history instead.

Although the culture of Britain in the period was mainly derived from Roman and Celtic sources, there were also Saxons settled as foederati in the area, originally from Saxony in northwestern Germany, although the term 'Saxon' was used by the British for all Germanic incomers. Gradually the latter assumed more control (see Anglo-Saxon England). The Picts in northern Scotland were outside the applicable area.

The period of sub-Roman Britain traditionally covers the history of the area which subsequently became England from the end of Roman imperial rule 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 the West of England (see Cornwall and Cumbria) and in Wales.

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