The Danish Viking army of Ivar the Boneless first took York in 866, but occupation was at first intermittent. After the victory of Alfred the Great over the Viking leader Guthrum in 878, the division of England became more formalized; the Danelaw, the territory where the Vikings held sway, ran from East Anglia to Northumbria and its de facto capital was York. Under the treaty confirming Danelaw, Guthrum converted to Christianity, and the Vikings maintained and, where necessary, rebuilt York’s churches. They also restored the walls of the decaying Roman fortress (the Anglian tower appears to have been a lookout point), creating a fortified ecclesiastical and administrative area covering some 50 acres, and housing the regal palace. Recent excavations reveal a prosperous and sophisticated commercial centre between the fortress and the Ouse. The last Viking ruler of York, Erik Blood Axe, was expelled in 954.
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