Bleddyn ap Cynfyn

Bleddyn ap Cynfyn (Middle Welsh: Bledẏnt uab Kẏnỽẏn; (died 1075), sometimes spelled Blethyn, was an 11th-century Welsh king. King Harold Godwinson and Tostig Godwinson installed Bleddyn and his brother, Rhiwallon, as the co-rulers of kingdom of Gwynedd on his father's death in 1063, during their destruction of the kingdom of their half-brother, king Gruffydd ap Llywelyn. Bleddyn became king of Powys and co-ruler of the Kingdom of Gwynedd with his brother Rhiwallon from 1063 to 1075. His descendants continued to rule Powys as the House of Mathrafal.

Background

Bleddyn was born to a poorly documented Powys nobleman named Cynfyn ap Gwerystan, known only from the late traditional pedigrees reporting Bleddyn's parentage. Cynfyn's claimed father, Gwerstan or Gwerystan, is given contradictory Welsh pedigrees consisting mostly of otherwise unknown names, a possibly spurious derivation since his name perhaps actually represents a rendering of the Anglo-Saxon name Werestan.

Cynfyn, likely a supporter of King Llywelyn ap Seisyll, would after the latter's 1023 death marry the widowed queen, Angharad, daughter of King Maredudd ab Owain of Dyfed, member of the House of Dinefwr, whose realm had been lost to the Irish pretender Rhain before its conquest by Llywelyn.

Angharad and Cynfyn had at least two sons, Bleddyn and Rhiwallon, probably born in the late 1020s, who were thus maternal half-brothers of Gruffydd ap Llywelyn, Angharad's son by her first husband. Gruffydd, aged about ten and passed over for succession at the time of his father's death, slowly rebuilt his father's realm, annexing its successor states.

Cynfyn and Rhiwallon first appear in the documentary record in 1063.