Xueyantuo

Xueyantuo (薛延陀) or Syr-Tardush were an ancient Tiele people and khanate in central/northern Asia who were at one point vassals of Tujue, who later aligned with China's Tang Dynasty against Eastern Tujue. After Eastern Tujue's Jiali Khan Ashina Duobi was defeated by Tang in 630, Xueyantuo effectively took over control of Eastern Tujue's former territory, at times submissive to Tang and at times warring with Tang and the subsequent khan of Eastern Tujue that Tang supported, the Qilibi Khan Ashina Simo. Eventually, in 646, the Jialijiulishixueshaduomi Khan, Bazhuo, was killed by the Huihe and a Tang army led by the general Li Daozong the Prince of Jiangxia crushed Xueyantuo forces. The last khan, the Yitewushi Khan Duomozhi, surrendered. The Huihe took over former Xueyantuo territory. For a (disputed) relationship with the later Shatuo Turks, see here.
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