Dulo clan
Western Turkic Khaganate was modernized through an administrative reform of Ashina clan (reigned 634–639) and came to be known as the "Onoq". The name refers to the "ten arrows" that were granted by the khagan to ten leaders ("shads") of its two constituent tribal confederations, the Duolu (five "churs") and Nushibi (five "irkins"), whose lands were divided by the Chui River. The division fostered the growth of separatist tendencies. Soon, chieftain Kubrat of the Dulo clan, whose relation ship with the Duolu is possible but not proven, seceded from the Khaganate. The Tang dynasty campaigned against the khaganate and its vassals, the oasis states of the Tarim Basin. The Tang campaign against Karakhoja in 640 led to the retreat of the Western Turks, who were defeated during the Tang campaigns against Karasahr in 644 and the Tang campaign against Kucha in 648, leading to the 657 conquest of the Western Turks by the Tang general Su Dingfang. Emperor Taizong of Tang was proclaimed Khagan of the Göktürks.