After Rome

The Romans did not leave Britain in a single year. Authority drained away across decades — the army drawn off, the coin and the pay drying up, command becoming local. On the Wall the story is not a sudden emptiness but a slow handover: garrisons that became warbands, forts that grew timber halls, a Brittonic north that gave way to the Anglian kingdom of Bernicia, and finally to Northumbria, Bamburgh and Lindisfarne. Here is what we can say — and, just as carefully, what we cannot.