Owain ap Gruffudd was King of Gwynedd, North Wales, from 1137 until his death in 1170, succeeding his father Gruffudd ap Cynan. He was called Owain the Great and the first to be styled "Prince of Wales", and the "Prince of the Welsh". He is considered to be the most successful of all the North Welsh princes prior to his grandson, Llywelyn the Great. He became known as Owain Gwynedd to distinguish him from the contemporary king of Powys Wenwynwyn, Owain ap Gruffydd ap Maredudd, who became known as Owain Cyfeiliog.

Llywelyn ab Iorwerth, also known as Llywelyn the Great, was a medieval Welsh ruler. He succeeded his uncle, Dafydd ab Owain Gwynedd, as King of Gwynedd in 1195. By a combination of war and diplomacy he dominated Wales for 45 years.