Selenga River
From AD 648–657, the Uyghurs, under Porun Ilteber (婆闰), worked as mercenaries for the Chinese in their annexation of the Tarim Basin. In AD 683, the Uyghur leader Dujiezhi was defeated by Göktürks and the Uyghur tribe moved to the Selenga River Valley. From this base, they struggled against the Second Göktürk Empire.