Sub-Roman Britain is the period of late antiquity in Great Britain between the end of Roman rule and the Anglo-Saxon settlement. 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 commenced with the recall of Roman troops to Gaul by Constantine III in 407 and to have concluded with the Battle of Deorham in 577. Meaning of terms The period of sub-Roman Britain traditionally covers the history of the area which subsequently became England 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. This period has attracted a great deal of academic and popular debate, in part because of the scarcity of the written source material. The term "post-Roman Britain" is also used for the period, mainly in non-archaeological contexts; "sub-Roman" and "post-Roman" are both 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; it is less successfully applied to Britain at the time. 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. Written accounts There is