Osulf or Oswulf was the son of Eadwulf IV, Earl of Bamburgh, and grandson of Uhtred the Bold, ruler of Bamburgh and ealdorman of Northumbria. Oswulf’s family ruled Bamburgh from 954 until 1041, though their independence may have been compromised after 1041 when Siward the Stout killed Eadwulf and gained hegemony over the north.