 Between 1211 and 1212, William, as Warden of Moray (or "Guardian of Moray") fought against the insurgency of Gofraid mac Domnaill (of the Meic Uilleim family), whom William beheaded in Kincardinein 1213.Upon finally destroying the Meic Uilleim's in 1229, he was given the Lordship of Badenoch and the lands it controlled.From an unknown date, William held the title Lord of Kilbride.