Iorwerth Drwyndwn

Iorwerth mab Owain Gwynedd, known as Iorwerth Drwyndwn ('the flat-nosed'; c. 1130 – 1174), was the eldest legitimate son of Owain Gwynedd (the king of Gwynedd) and his first wife Gwladus ferch Llywarch. He married Marared ferch Madog. His son Llywelyn ab Iorwerth eventually united the realm and became known as Llywelyn Fawr ('the Great'); he is one of Wales's most famous monarchs. Iorwerth received Nant Conwy as his inheritance from his father, Owain Gwynedd. However, he did not receive the crown succession, as was the normal tradition, because of his nose defect.

J. E. Lloyd states that Iorwerth was killed in battle at Pennant Melangell, in Powys, in 1174 during the wars deciding the succession following the death of his father.