Ashina Helu
Ishbara Khagan was the last khagan of the Western Turkic Khaganate.
Name
His underlying Turkic name, transcribed with Chinese characters 賀魯, was debated among scholars. Gumilyov proposed Hallïğ, meaning "Elevated". Von Gabain proposed name Kullïğ. Gömeç argued for Uluğ meaning "Great". Meanwhile, Kapusuzoğlu proposed Kutluğ as his underlying Turkic name. Zuev linked the Khagan personal name Helu with the tribal name Khallukh attested by Persian and Arab writers, and asserted that by the 7th century Helu's tribe was dynastic; later, however, Zuev proposed that Chinese Helu reflects Turkic *aru ~ arïğ "pure, light".Biography
Early years
Ashina Helu's parentage is uncertain. According to Gumilov his father was Böri Shad, however Chavannes attributes him as a son of Irbis Seguy. He was awarded with the title shad by Duolu Qaghan in 633 and appointed to govern certain tribes including the Chuye, Qarluq, Nushibi. In 646 he rose against Irbis Seguy only to be defeated by him. He fled to China on 25 April 648 and served the Tang dynasty as a general stationed in Mohe city in Gansu.However he planned to assert independence using Taizong's death in 649. Qiao Baoming personal staff of Gaozong tried to avert it by ordering him to deliver his son Ashina Xiyun to serve in the palace guard. Xiyun served for a while before returning to Helu again and encouraging him to attack Irbis Dulu Qaghan.
Reign
After a while he set up his horde near modern Shuanghe and began to receive submissions. According to the Zizhi Tongjian firstly the Duolu tribe chiefs who were titled as čor, namely Chomuqun chief Kuli, Ulugh Oq chief Kul, Chapshata chief Ton, Türgesh-Halach chief, Shungish chief Chuban submitted. Ulugh Oq chief was also a son-in-law to Helu. Nushibi tribal chiefs who were titled irkin also submitted; Esegel chief Kül, Geshu chief Kül, Basaigan chief Tong Ishbara, Esegel chief Nishu, Geshu chief Chuban. Ashina Xiyun was appointed crown prince with the title Bagatur Yabgu.After formally reasserting independence from the Tang, he commanded raids to Jin Ling and Pulei. Emperor Gaozong stripped him of Chinese titles and ordered Qibi Heli and Liang Jianfang to secure border areas.
Conflicts also began in southern border when Zhenzhu Yabgu started major incursions to Western Turkic territory. Later Zhenzhu contacted the Tang to receive soldiers and requested to be made a khagan in 655. Yuan Lichen was ordered by Gaozong to visit Zhenzhu on 8 November 656 to make him khagan, but he was stopped by Helu's soldiers near Suyab, causing Zhenzhu to lose much prestige.
In 657 Emperor Gaozong started the Conquest of the Western Turks. General Su Dingfang was appointed to be leading commander during whole operation. The Chumukun tribe was first to lose whose chief Lantulu submitted. The Tang army defeated Ashina Helu at the Battle of Irtysh River. However he fled to Chach with his son Ashina Xiyun and a noble retainer Xuyan. However he was soon handed over to Xiao Siya by Chach ruler Yixian Tarkhan.
Later years
After being captured he reportedly told Xiao Siya:Emperor Gaozong spared him after 15 days and he lived out his days at the Tang capital Chang'an. He was buried near Illig Qaghan's memorial.