Rhiwallon ap Cynfyn

Rhiwallon ap Cynfyn († 1070) was, together with his brother Bleddyn rulers of the Welsh principality of Gwynedd and Powys.

He was the second son of Cynfyn ap Gwerstan, a nobleman from Powys and Angharad, widow of Llywelyn ap Seisyll and daughter of Maredudd from Owain, King of Deheubarth. About his mother, he was a half-brother Gruffydd ap Llywelyn of the Welsh princes. After the death of her half-brother Gruffydd the Anglo-Saxon King Edward the Confessor made ​​his brother Bleddyn and vassal kings of Powys and Gwynedd him in 1064. He fell in 1070 at the Battle of Mechain in the fight against Gruffydds sons of Maredudd and Ithel, both of which also fell. His brother Bleddyn remained until his death in 1075 ruler of Gwynedd and Powys.

He left two sons and two daughters. His sons supported Bleddyns cousin and successor Trahern ap Caradog. One of my sons, Cynwrig ap Rhiwallon fell in 1075 in the fight against Gruffydd ap Cynan at Clynnog Fawr in North West Wales. His other son Meilyr fell in 1081 along with Trahern ap Caradog at the Battle of Mynydd Carn in the struggle against Rhys ap Tewdwr of Gwynedd and Gruffydd ap Cynan Deheubarth. Rhiwallons daughter married Rhys ap Tewdwr Gwladus.