performance this time was apparently more satisfactory and by 1238 he had been given the remainder of Llŷn and a substantial part of Powys. Death and the transfer of power Joan died in 1237 and Llywelyn appears to have suffered a paralytic stroke the same year. From this time on, his heir Dafydd took an increasing part in the rule of the principality. Dafydd deprived his half-brother Gruffydd of the lands given him by Llywelyn, and later seized him and his eldest son Owain and held them in Criccieth Castle. The chronicler of Brut y Tywysogion records that in 1240, "the lord Llywelyn ap Iorwerth son of Owain Gwynedd, Prince of Wales, a second Achilles, died having taken on the habit of religion at Aberconwy, and was buried honourably." Llywelyn died at the Cistercian abbey of Aberconwy, which he had founded, and was buried there. This abbey was later moved to Maenan, becoming the Maenan Abbey, near Llanrwst, and Llywelyn's stone coffin can now be seen in St Grwst's Church, Llanrwst. Among the poets who lamented his passing was Einion Wan: Dafydd succeeded Llywelyn as prince of Gwynedd, but King Henry was not prepared to allow him to inherit his father's position in the remainder of Wales. Dafydd was forced to agree to a treaty greatly restricting his power and was also obliged to hand his half-brother Gruffydd over to the king, who now had the option of using him against Dafydd. Gruffydd was killed attempting to escape from the Tower of London in 1244. This left the field clear for Dafydd, but Dafydd himself died with illegitimate and underage issue in 1246 and was eventually succeeded by his nephew, Gruffydd's son, Llywelyn ap Gruffudd. Historical assessment Llywelyn dominated Wales for more than 40 years, and was one of only two Welsh rulers to be called "the Great", the other being his ancestor Rhodri the Great. The first person to give Llywelyn the title "the Great" seems to have been his near-contemporary, the English chronicler Matthew Paris. J. E. Lloyd gave the following assessment of Llywelyn: Among the chieftains who battled against the Anglo-Norman power his place will always be high, if not indeed the highest of all, for no man ever made better or more judicious use of the native force of the Welsh people for adequate national ends; his patriotic statesmanship will always entitle him to wear the