)Following the defeat of Edwin at the Battle of Hatfield Chase in 633 against Penda of Mercia and Cadwallon ap Cadfan, and the subsequent despoliation of Northumbria, Æbbe's brother Oswald gained control of the kingdom by 635 AD, enabling the return of his family.In c. 635 King Oswald introduced Columban monks to the island of Lindisfarne, opposite his fortress of Bebbanburg, in order to Christianise his mainly pagan peoples.