Iorwerth ap Cadwgon

Iorwerth ap was born about 1020 in Buillth, Breconshire, Wales.  Iorwerth ap's father was Cadwgon ap Elystan and his mother was Efa verch Gwrgan. He had a sister named Joan verch.  He was the older of the two children. He had a half-brother named Idnerth ap.

They had a son and a daughter, named Llewelyn ap and Dyddgu verch.