The Battle of Bolchu (711)

In the early 8th century the Türgesh grew strong and sought alliances with the Tang and the Kyrgyz against the Second Turkic Khaganate. Zhenu, brother of the Türgesh khagan Saqal, quarrelled with him and fled to the Turkic khagan Qapaghan. At the time Qapaghan was fighting the Khitans in the east, and his khatun had just died.

Qapaghan put his old minister Tonyukuk in command, with his son Inel and his nephews Bilge and Kül Tigin. According to the Tonyukuk inscription the Türgesh army was very large and frightened the Turkic nobles, but Tonyukuk attacked without hesitation. In 711, near the Bolchu river in Dzungaria, he defeated the Türgesh after two days of fighting.

The Türgesh khagan Saqal was captured and killed, and the Türgesh lands came for a time under Turkic rule. The Turkic army then pushed west as far as the Iron Gate, a campaign recalled with pride in the Kül Tigin and Tonyukuk inscriptions.