Llywelyn ab Iorwerth is known to history as ‘the Great’, and the epithet reflects the fact that he united more of Wales under his rule than any of his predecessors.
Grandson of the powerful Welsh ruler Owain Gwynedd, Llywelyn became involved in a dynastic power struggle at an early age. By 1200 he had ousted Dafydd and Rhodri, his two uncles and chief challengers for the throne of Gwynedd. When his cousin, Gruffudd ap Cynan, died that same year, Llywelyn became the undisputed ruler of north Wales. One of his first diplomatic moves was to ally himself with King John of England, an alliance which he consolidated five years later by marrying John’s illegitimate daughter, Joan. Over the next few years he added considerably to his territories in Wales.
By 1211, however, relations with the English Crown had soured, and John invaded Gwynedd with the intention of crushing Llywelyn once and for all. The pleading of Joan on her husband’s behalf kept Llywelyn in power, but his influence was greatly diminished and he lost all his lands east of the River Conwy. By 1216, however, Llywelyn had become the dominant ruler in Wales once more, and he remained so until his death. By around 1230 he was styling himself ‘Prince of Aberffraw and Lord of Snowdonia’, but in fact his dominion went beyond Anglesey and north Wales.
Traces of Llywelyn’s 39-year reign are still to be seen in the Welsh landscape today, in the form of the great castles of Criccieth, Dolbadarn, Dolwyddelan, and Castell y Bere. They were built to defend the vital roads into Snowdonia and the royal pasturelands on which the economy of north Wales depended. Llywelyn also founded several monasteries and fostered a particularly close relationship with the Cistercian monks of Aberconwy Abbey. It was there that he died and was buried, having suffered a stroke.