Xueyantuo
The Xueyantuo (薛延陀) (Seyanto, Se-yanto, Se-Yanto) or Syr-Tardush were an ancient Tiele people and khanate in central/northern Asia who were at one point vassals of the Gokturks, later aligning with China's Tang Dynasty against the Eastern Gokturks. Xueyantuo started from Selenga River/Xueyanhe River (薛延河江/偰輦河江), so tribe name is Seyanto/Xueyantuo (薛延陀), Chinese Han character undergo considerable revision by rise and fall of Chinese Dynasty, so have many name as Xueyantuo, Xueyanhe, Xienianhe, Seyanto, Selenga, Selyanha, etc. .
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