What happened in britain after roman armies abandoned the area during the 400s?

Britain was under Roman control but When the Romans retreated from Britain, the barbarians started to attack . Since the roman army had  already retreated from Britain, under the generalship of Constantine third. Some of the groups such as Picts of Scotland had attacked Britain in the past, and some groups who didn't have a history of attacking Britain started to do so during the first half of the fifth century. The first time attackers were the Angles and Saxons and the Jutes.

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