Owain Gruffydd was the archetypal medieval Welsh prince, warlike and powerful.
Born in about 1100, Owain ap Gruffydd of Gwynedd (shortened to Owain Gwynedd to distinguish him from a contemporary prince of Powys called Owain ap Gruffydd) is considered to be one of the foremost monarchs of Gwynedd as he ruled most of Wales.
Owain became the heir to the kingdom of Gwynedd in 1132, on the death of his older brother Cadwallon in battle. He proved himself in battle a capable warlord, and he and his other brother Cadwaladr added lands to their father's kingdom.
Owain acceded the throne in 1137, sharing it with with Cadwaladr until 1143 when his brother was involved in the murder of a prince of Deheubarth.
Owain ruled Gwynedd as a sole monarch, and used the chaos of the civil war in England between the supporters of Stephen and Matilda to stretch his borders into Marcher lands, as well as successfully invading Powys.
In 1157, the new king, Henry II, invaded Gwynedd with no overall victory, but Owain was forced to come to terms with the English monarch.
Owain wasn't going to lie low for ever, and in 1165 an alliance with Deheubarth resulted in a challenge to Henry. Owain, together with the majority of Welsh princes, met Henry in battle, but his army were more defeated by Wales' weather than its native's skills on the battlefield.
Henry was not to invade Wales or challenge Owain again, and he died a powerful ruler in 1170.