The Battle of the Defile was fought over three days in July 731 in and near the Takhtakaracha Pass (in modern Uzbekistan) between a large army of the Umayyad Caliphate and forces of the Türgesh Khaganate. The Türgesh had been besieging Samarkand; Samarkand's commander, Sawra ibn al-Hurr al-Abani, sent a request for relief to the newly appointed governor of Khurasan, Junayd ibn Abd al-Rahman al-Murri. Junayd's 28,000-strong army was attacked by the Türgesh in the pass, and although the Umayyad army managed to extricate itself and reach Samarkand, it suffered heavy casualties. Sawra's 12,000 men attacked the Türgesh from the rear in a relief effort and were almost annihilated. The battle halted and even reversed Muslim expansion into Central Asia for a decade. In addition, it increased Khurasani disaffection for the Umayyad regime, and drew away reinforcements from the metropolitan regions of the Caliphate, helping to bring about its downfall twenty years later. (Full article...)