From Wikipedia
Eric (Eiríkr) Haraldsson, nicknamed Bloodaxe (blóðøx), is thought to
have had short-lived terms as the second king of Norway and as the last
independent ruler of the Kingdom of Northumbria.
The Northumbria on which Eric set foot was one which had been bitterly
fought over between the West-Saxon kings and the Hiberno-Norse line of
descendants from Ímair, kings of Dublin.