Bleddyn ap Cynfyn
| Bleddyn ap Cynfyn | |
|---|---|
| King of Gwynedd | |
| Reign | 1063–1075 |
| Predecessor | Gruffydd ap Llywelyn |
| Successor | Trahaearn ap Caradog |
| King of Powys | |
| Reign | 1063–1075 |
| Predecessor | Gruffydd ap Llywelyn |
| Successor | Iorwerth ap Bleddyn |
| Died | 1075 |
| Spouse | Haer ferch Gillyn |
| House | Mathrafal |
| Father | Cynfyn ap Gwerystan |
| Mother | Angharad ferch Maredudd ap Owain |
Bleddyn ap Cynfyn (Old 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.