Question: Who is the paternal grandfather of Cadfan Ap Cadwaladr?
Sentence (from "Cadwallon ap Cadfan"): The son and successor of Cadfan ap Iago, he is best remembered as the King of the Britons who invaded and conquered the Kingdom of Northumbria, defeating and killing its king, Edwin, prior to his own death in battle against Oswald of Bernicia.
Relevant evidence: No