In 410 the Roman emperor, Honorius, told the local authorities in Britain that he could not send any reinforcements to help them defend the province against ‘barbarian’ attacks.
The Roman armies on the continent were overstretched, fighting both the tribes who had come over the Rhine and Danube frontiers and also the Roman generals (including some from Britain) who wanted to control the empire themselves.
Roman Britain was being attacked from three directions. The Irish (called ‘Scotti’ by the Romans) attacked from the west; the Picts from the north; and various Germanic-speaking peoples from the east, across the North Sea. The latter included the Angles, Saxons and Jutes, who were all from northern Germany or southern Denmark.
The continental invaders were generally called ‘Saxons’ by their neighbours. England is still called ‘Sasana’ in Gaelic, and its inhabitants are ‘Sassenachs’.
The term ‘Anglo-Saxon’ did not become common until the eighth century, when people on the continent started using it to distinguish between the inhabitants of Britain and the Saxons who remained in northern Germany.
The Anglo-Saxons themselves had by then begun to use the word ‘Angli’ or ‘English’ to refer to themselves.
The Romano-Britons defended themselves against the invaders as best they could, with successful military leaders including Ambrosius Aurelianus and the possibly entirely legendary figure of Arthur.
New kings emerged to rule different kingdoms within the former Roman province. One hundred and fifty years after the end of Roman rule, some were still taking Roman names like Constantine and Aurelius.