Zengi Against Damascus
Following the death in 1128 of Toghtekin, atabeg of Damascus, a power vacuum threatened to open Syria to renewed Crusader aggression.
Zengi became atabeg of Mosul in 1127, and of Aleppo in 1128, uniting the two cities under his personal rule, and was formally invested as their ruler by the Sultan Mahmud II of Great Seljuk. Zengi had supported the young sultan against his rival, the caliph Al-Mustarshid.
In 1130 he allied with Taj al-Mulk Buri of Damascus against the crusaders, but this was only a ruse to extend his power; he had Buri's son taken prisoner and seized Hama from him. He also besieged Homs, the governor of which was accompanying him at the time, but could not capture it, so he returned to Mosul, where Buri's son and the other prisoners from Damascus were ransomed for 50,000 dinars. In 1131 Zengi agreed to return the 50,000 dinars if Buri would deliver to him Dubays ibn Sadaqa, emir of al-Hilla in Iraq, who had fled to Damascus to escape al-Mustarshid. When an ambassador from the caliph arrived to bring Dubais back, Zengi attacked him and killed some of his retinue; the ambassador returned to Baghdad without Dubais.
In 1134 Zengi became involved in Artuqid affairs, allying with the emir Timurtash (son of Ilghazi) against Timurtash's cousin Da'ud. Zengi's real desires, however, lay to the south, in Damascus. In 1135 Zengi received an appeal for help from Ismail, who had succeeded his father Buri as emir of Damascus, and who was in fear for his life from his own citizenry who considered him a cruel tyrant. Ismail was willing to surrender the city to Zengi in order to restore peace. None of Ismail's family or advisors wanted this, however, and Ismail was murdered by his own mother, Zumurrud, to prevent him from turning over the city to Zengi's control. Ismail was succeeded by his brother Shihab ad-Din Mahmud.
Zengi was not discouraged by this turn of events and arrived at Damascus anyway, still intending to seize it. The siege lasted for some time with no success on Zengi's part, so a truce was made and Shahib ad-Din's brother Bahram-Shah was given as a hostage. At the same time, news of the siege had reached the caliph and Baghdad, and a messenger was sent with orders for Zengi to leave Damascus and take control of the governance of Iraq. The messenger was ignored but Zengi gave up the siege, as per the terms of the truce with Shahib ad-Din. On the way back to Aleppo, Zengi besieged Homs, whose governor had angered him, and Shahib ad-Din responded to the city's call for help by sending Mu'in ad-Din Unur to govern it.
Read more about this topic: Imad Ad-Din Zengi