Ulf was the son of Harold Godwinson. His mother was possibly Ealdgyth, Harold’s second wife, but may have been Edyth Swanneck. Ulf and Harold may have been twins. He was likely born after his father’s death and it is likely that he lived in exile on the continent after his father’s death at the Battle of Hastings.
Family tree for Harold Haroldson, son of Harold Godwinson showing: