 There is no record of Iorwerth having taken part in the power struggle between some of Owain Gwynedd's other sons following Owain's death, although he was the eldest surviving son.There is a tradition that he was disabled or disfigured in some way that excluded him from power.Lloyd states that he was killed in battle at Pennant Melangell, in Powys, in 1174 during the wars deciding the succession following the death of his father.