 In the 5th century the Turks began to emerge in the Altay region, subservient to the Rouran.Within a century they had defeated the Rouran and established a vast Turkic Khaganate (552–581), stretching over most of Central Asia past both the Aral Sea in the west and Lake Baikal in the east.In 581 the Gokturks split into the Western Turkic Khaganate (581–657) and Eastern Turkic Khaganate (581–630), with Xinjiang coming under the western half.