Gwenwynwyn ab Owain Cyfeiliog (died c. 1216) was the last major ruler of mid Wales before the completion of the Norman English invasion. He was one of few native rulers to represent a real threat to the rule of Llywelyn the Great.
Lineage
Gwenwynwyn ruled southern Powys (Powys Wenwynwyn) from 1195, and was given charge of the kingdom following the retirement of his father Owain Cyfeiliog. Prior to this, in 1187, he had made an attack on Carreghofa Castle with his brother Cadwallon, in the course of which they killed their father's cousin and former ally, Owain Fychan.
Owain Cyfeiliog had been a notable poet as well as a leader of the resistance against English invasion, and chose to enter the abbey of Strata Marcella in later life; he died in 1197, two years after becoming a monk. Gwenwynwyn continued his father's strategy and is thought to have been one of the Welsh rulers who made an agreement with King Richard I of England not to attack his kingdom while he was away on crusade. In 1199, he made peace with Richard's successor, John. He was rewarded with marriage to an English noblewoman, Margaret Corbet, the daughter of the Lord of the border territory of Caus, around 1200, as well as the grant of the manor of Ashford.
Gwenwynwyn's lands were restored to him as a result of John's intervention after two years. Gwenwynwyn was pursued by Llywelyn, who took his lands, and he took refuge in Chester.
Death and legacy
Llywelyn invaded Powys, backed by other leaders of the Welsh alliance against the English. Gwenwynwyn, having been driven out of his lands, is believed to have died or been killed later that same year. He was succeeded by Gruffydd ap Gwenwynwyn, his son by Margaret Corbet, who was eventually restored to his lands after Llywelyn's death, and continued to feud with the princes of Gwynedd.