The policy of Tang China was to vassalize all people to the north of Chinese border line and Özmiş Khagan was also expected to pay respect. Initially, Özmiş agreed to visit emperor Xuanzong’s court and pay respect to the emperor, but then he changed his mind and tried to keep his independence. His reluctance annoyed the emperor and the emperor tasked his general Wang Zhongsi (王忠嗣) to arrest Özmiş. Wang Zhongsi organized a coalition of three Turkic people Basmyl, Uighur and Karluk, who had previously accepted the suzerainty of Chinese emperor, instead of Özmiş.
The coalition defeated Özmiş Khagan. Although Özmiş escaped he was soon defeated for the second time and was killed in 744 by Ashina Shi himself.[5]
Although the Turkic people elected Özmiş’s son Kulun Beg as their new khagan, his empire is usually considered to be collapsed by the death of Özmiş.
In 742, with the Karluks and Uyghurs support, he was declared as the new Khagan. Ashina Shi used the title 'Ydyk-kut' which can be translated as 'Heaven Sent'[6]. Later he appointed Karluks to leadership of right wing and Uyghurs to leadership of left wing. However, he was soon deposed by Uyghurs, which signalled beginning of Uyghur Empire.
^S.G. Klyashtorny, "Ancient Turk Rock Inscriptions in the Talas Ala-Too. A Sogdian Word in an Old Turk Inscription", Webfestschrift Marshak 2003, (Online Article).
