Mu‘in al-Din Unur, atabeg of Damascus (1138-1149). Unur was originally a Turcoman mamlûk (slave soldier) of Tughtigin, atabeg of Damascus (d. 1128). He came to power in a coup in April 1138, and until his death was atabeg and army commander (Arab. isfahsālār) under three successive rulers (“kings”): Mahmûd ibn Bûri (d. 1139), Muhammad ibn Būrī (d. 1140), and Abaq ibn Muhammad.
Up to 1146-1147, Unur’s policies were characterized by resistance to Zangi, atabeg of Mosul, and cooperation with the Franks of the kingdom of Jerusalem. When Mahmûd ibn Būrī was murdered in June, probably at the instigation of Zangi, Unur managed to keep Damascus secure by smoothly transferring the government to Muhammad ibn Būrī. The latter died during a seven-month siege of the city by Zangi (1139-1140), and Unur installed Muhammad’s young son Abaq as the new sovereign. Unur obtained help from King Fulk of Jerusalem, offering him 20,000 dinars per month during the campaign and the surrender of the strategic town of Banyas. Zangi abandoned the siege at the approach of the Frankish army. The alliance between Damascus and Jerusalem lasted until 1147. In that year, Unur gave his daughter in marriage to Nûr al-Din, Zangi’s son and successor, which led to an improvement in relations between the two rulers.
Later in the year, Queen Melisende of Jerusalem abandoned the long-standing alliance with Damascus and supported a rebellion against Unur by one of his vassals in Bosra. Unur joined with Nûr al-Din, and their combined forces inflicted a heavy defeat on the Franks during the summer; Unur prevented the Turcoman troops from pursuing the defeated Franks. On 24 July 1148 Unur successfully defended his city against the siege mounted by the combined armies of the kingdom of Jerusalem and the Second Crusade (1147-1149), having obtained military assistance from Mosul and Aleppo for help. He welcomed the truce for two years proposed in May 1149 by the kingdom of Jerusalem, which enabled him to continue his policy of keeping the balance of power between the Franks and the Turkish powers in the north. Unur died on 28 August 1149, and Damascus suffered long economic warfare by Nûr al-Din until it was forced to surrender to him in 1154.