Llywelyn ap Gruffudd

Llywelyn ap Gruffudd became Prince of Gwynedd in 1255 and spent the next two years pushing successful campaigns across Wales. In 1258 he proclaimed himself Prince of Wales, a title Henry III formally recognized in the Treaty of Montgomery nine years later. The recognition held for fifteen years, until Edward I began his conquest of Wales. On 11 December 1282, Llywelyn died in an ambush at Cilmeri, one of the final acts in Edward's campaign to absorb Wales into the English crown.