Meanwhile, Joscelin II paid little attention to the security of his county, and argued with the counts of Tripoli who then refused to come to his aid. Zengi besieged the city in 1144, capturing it on December 24 of that year. Joscelin continued to rule his lands west of the Euphrates, and he also managed to take advantage of the death of Zengi in September 1146 to regain and briefly hold his old capital. The city was again lost in November, and Joscelin barely escaped. In 1150 he was captured by Zengi's son Nur ad-Din, and was kept a prisoner in Aleppo until he died in 1159. His wife sold Turbessel and what was left of the County to the Byzantine Emperor Manuel I Comnenus, but these lands were conquered by Nur ad-Din and the Sultan of Rum within a year. Edessa was the first Crusader state to be created, and also the first to be lost.