Civil war and split of the Turkic Khaganate

Dying in 581, Taspar told his son Anluo to yield the throne to Daluobian, a son of the earlier khagan Muqan. The Book of Sui relates that the nobles rejected Daluobian because his mother was of low birth; Shetu, a grandson of Bumin, threatened to meet his election with sharp blades and long spears, and Anluo, unable to control his resentful rival, gave up the throne to Shetu. As Ishbara Qaghan, Shetu ruled from Ötüken; Anluo became a “second khagan” on the Tuul, Daluobian received the title of Apa Qaghan, and Tardu, the son of Istämi, held the west. Ishbara’s wife, a princess of the Northern Zhou, urged him to avenge her family on the new Sui dynasty, and in 582 he invaded China with, the Book of Sui says, 400,000 archers; the Sui answered with armies and with diplomacy, and the envoy Zhangsun Sheng set about sowing discord among the Turkic princes.

In 583 Ishbara, jealous of Apa’s valour, fell upon his camp and killed his mother. Apa fled west to Tardu, who gave him troops, and the Book of Sui dates the division of the Turks into two from this feud. Pressed from the west and fearing the Khitans in the east, Ishbara accepted the overlordship of the Sui in 584–585 and with their help defeated Apa; after Ishbara’s death in 587 his brother Chuluohou (Bagha Qaghan) captured Apa. In 599, when the eastern khagan Dulan was killed by his own men, Tardu proclaimed himself supreme khagan, but the Sui backed his rival Qimin Qaghan, and a revolt of the Tiele tribes stripped Tardu of his followers; in 603 he fled to the Tuyuhun and disappeared.

The two halves were never reunited. The Eastern Turks, still ruled from Ötüken, were conquered by Tang China in 630; the Western Turks, to whom, the Book of Sui says, Kucha, Yiwu and the peoples of the Western Regions submitted, were conquered by the Tang in 657. The crisis began with Taspar’s death in 581; open war broke out in 583, which is why the civil war is often dated 583–603.