Battle of Irtysh River

This article is about the battle between the Tang dynasty and the Western Turkic Khaganate. For the battle between the Mongol Empire and the Merkits and Naimans, see Battle of Irtysh River (1208/1209).

Battle of Irtysh River
Part of Tang campaign against the Western Turks
Date 657 Location Irtysh River Result Tang victory
Belligerents
Tang dynasty Former vassals of the Western Turks	Western Turkic Khaganate
Commanders and leaders
Su Dingfang Ren Yaxiang Ashina Mishe Ashina Buzhen Xiao Siye	Ashina Helu
Strength
unknown number main Tang army+10,000 Tang and Uyghur troops	100,000 troops

The Battle of Irtysh River (Chinese: 額爾齊斯河之戰) or Battle of Yexi River (Chinese: 曳咥河大戰) took place in 657 between Tang dynasty general Su Dingfang and the Western Turkic Khaganate qaghan Ashina Helu during the Tang campaign against the Western Turks. It was fought along the Irtysh River near the Altai Mountains. Su Dingfang deployed his infantry in the south, and cavalry in the north behind a hill. Helu's forces, consisting of 100,000 cavalry, surrounded and charged at the Chinese infantry three times, all of the charges were repelled. Then Helu's forces were ambushed by the Tang cavalry from the north. Helu was defeated during Su's surprise attack, and lost most of his soldiers. Turkic tribes loyal to Helu surrendered, and the retreating Helu was captured the next day.

Helu's defeat ended the Western Turkic Khaganate, strengthened Tang control of Xinjiang, and led to Tang suzerainty over the western Turks.