Criccieth Castle a distant relation of Llywelyn ap Gruffudd, began an uprising against English rule that spread quickly through Wales. Several English-held towns were razed and Criccieth (along with Harlech Castle and Aberystwyth Castle) were besieged that winter. Its residents survived until spring when the castle was resupplied. In the 14th century the castle had a notable Welsh constable called Hywel ap Gruffydd, known as Howell the Axe, who fought for Edward III at the Battle of Poitiers in 1356. The castle was used as a prison until 1404 when Welsh forces captured the castle during the rebellion of Owain Glyndŵr. The
Ieuan ab Owain Glyndŵr Ieuan ab Owain Glyndŵr Ieuan ab Owain Glyndŵr was reputedly the illegitimate son of the last native Welsh Prince of Wales; Owain Glyndŵr. The possibility of his existence was uncovered through the work of Peter Bartrum which is currently being edited by the University of Wales Aberystwyth. Ieuan ab Owain and his descendants are detailed in "Peniarth Manuscript 287" in the hand of Robert Vaughan of Hengwrt (c.1592-1667) and also in the manuscript known as "Harley 1969" by Griffith Hughes (1634–1665) - the original manuscripts are kept at the National Library of Wales, Aberystwyth and the British Library respectively. Ieuan,