Historia regum Anglorum identifies the commanders of the Vikings in 866 as Ivar, Ubba, and Halfdan. At just one level right after its account of Ubba's mentioned victory in excess of the Northumbrians, Historia de sancto Cuthberto expands upon the Vikings' profitable campaigning throughout Anglo-Saxon England, and exclusively identifies the Viking commanders as Ubba, dux of the Frisians, and Halfdan, rex of the Danes.