He appears in four charters in the Book of Llandaff during the episcopate of Bishops Euddogwy and Inabwy. Later, Gwrgan features as king in charters in the Book of Llandaff associated with Bishops Oudoceus and Iunapeius.
He appears in four charters within the Book of Llandaff during the episcopate of Bishops Euddogwy and Inabwy. Later, Gwrgan is depicted as a king in charters associated with Bishops Oudoceus and Iunapeius.