Rhiwallon ap Cynfyn , Prince of Powys

Rhiwallon ap was born in 1026 in Powys, Wales.  Rhiwallon ap's father was Cynfyn ap Gwerystan and his mother was Angharad verch Maredudd.  His paternal grandparents were Gwerystan ap Gwaithfoed , Baron Powys and Nest verch Cadell; his maternal grandparents were Maredudd ap Owain and Miss verch Llandilo. He had a brother and two sisters, named Bleddyn "Sais" ap, Miss verch and Iwerydd verch.  He was the youngest of the four children. He had a half-brother named Gruffudd ap.  He died at the age of 43 in 1069.

He had two biological daughters named Janet verch and Gwladus verch.