The first conflict between the Khazars and the Abbasids resulted from a diplomatic manoeuvre by the Caliph al-Mansur (). Attempting to strengthen the Caliphate's ties with the Khazars, in he ordered his governor of Armenia, Yazid al-Sulami, to marry a daughter of the "khagan" Baghatur. The marriage indeed took place amidst much celebration, but she died in childbirth two years later, along with her infant child. The "khagan" suspected the Muslims of poisoning his daughter, and launched devastating raids south of the Caucasus in 762–764. Under the leadership of a Khwarezmian "tarkhan" named Ras, the Khazars devastated Albania, Armenia, and Iberia, where they captured Tiflis. Yazid himself managed to escape capture, but the Khazars returned north with thousands of captives and much booty. A few years later, however, in 780, when the deposed Iberian ruler Nerse tried to induce the Khazars to campaign against the Abbasids and restore him to his throne, the "khagan" refused. This was probably the result of a brief period of anti-Byzantine orientation in Khazar foreign policy, resulting from disputes between the two powers in the Crimea. During the same period, the Khazars helped Leon II of Abkhazia throw off Byzantine overlordship.