قتيبة بن مسلم الباهلي
The region of Transoxiana had been conquered by the Umayyad leader Qutayba ibn Muslim in the reign of al-Walid I (), following the Muslim conquests of Persia and Khurasan in the mid-7th century. The loyalties of Transoxiana's native Iranian and Turkic populations and those of autonomous local rulers remained questionable, however, as demonstrated in 719, when the Transoxianian princes sent a petition to the Chinese and their Türgesh vassals for military aid against the Caliphate's governors.