of the Ayyubid possessions. It appears that as-Salih's son al-Muazzam Turanshah remained prince of Hisn Kayfa from 1238 until 1249. When as-Salih Ayyub died suddenly on 12 November 1249, Turanshah had to be recalled in a hurry to take control of the Ayyubid empire. As-Salih's widow, Shajar al-Durr, dispatched a special embassy to bring her son to Egypt. Turanshah had left Hisn Kayfa with this party by 18 December 1249, heading for Anah and Damascus. Al-Muwaḥḥid ʿAbd Allāh succeeded his father, Turanshah, as ruler of Hisn Kayfa. Although his father ruled Egypt for barely a year and was killed during the Mamluk takeover, al-Muwaḥḥid ʿAbd Allāh ruled Hisn Kayfa for more than three decades, from to , and was essentially the founder of the local Ayyubid dynasty. Although little remains standing from this prosperous period of the town's history, there is a detailed contemporary first-hand account by the topographer ʿIzz ad-Dīn Ibn Shaddād, whose last visit was in . He lists many buildings in the lower town, including a Dār as-Salṭana (near the bridge), a mosque, three medreses, four hammams, tombs, caravanserais and bazaars. At the citadel, Ibn Shaddād mentions another mosque, an open square, and fields to grow enough grain "to feed the inhabitants from year to year". The German historian of Islamic art Michael Meinecke notes that almost none of the buildings that Ibn Shaddād describes can be identified in present-day Hasankeyf, and attributes that to neglect following the subsequent Mongol invasions and political instability. In 1255, the great khan Möngke charged his brother Hulagu with leading a massive Mongol army to conquer or destroy the remaining Muslim states in southwestern Asia. Hulagu first besieged Baghdad, which was captured on 13 February 1258 and destroyed. He conquered Aleppo on 24 January 1260, and the Nestorian Christian Mongol general Kitbuqa Noyan took Damascus on 1 March. It seemed inevitable that all of the region's cities, including Hisn Kayfa, would fall to the Mongols, and indeed most of them did. Hulagu's plan appears to have been to proceed to Palestine and Egypt. But while he was in Aleppo in the spring of 1260, he received word that the great khan Möngke had died the previous summer (on 11 August 1259). While Hulagu did not expect to succeed his elder brother, there was a struggle between two of his other brothers, Kubilai and Ariq Böke, for control of the Mongol empire,