Battle of Huo-i

Battle of Huoyi
Part of the transition from Sui to Tang
Map of the situation in China during the transition from the Sui to the Tang, with the main contenders for the throne and the main military operations by the Tang and their various rivals
Date 8 September 617 Location Huoyi, in modern Linfen, Shanxi Result Victory for Li Yuan
Belligerents
Li Yuan's forces	Sui dynasty
Commanders and leaders
Li Yuan Li Shimin Li Jiancheng	Song Laosheng  (POW)
Strength
ca. 25,000	20,000 or 30,000

The Battle of Huoyi (霍邑之戰; Wade-Giles: Huo-i) was fought in China on 8 September, 617, between the forces of the rebel Duke of Tang, Li Yuan, and the army of the ruling Sui dynasty. Li Yuan, with an army of around 25,000, was advancing south along the Fen River towards the imperial capital, Daxingcheng. His advance was stalled for two weeks due to heavy rainfall and he was met at the town of Huoyi by an elite Sui army of 20,000 (or 30,000) men. Li Yuan's cavalry, under the command of his two eldest sons, lured the Sui out of the protection of the city walls, but in the first clash between the two main armies, Li Yuan's forces were initially driven back. At that point, possibly due to a stratagem on Li Yuan's behalf, the arrival of the rest of the rebel army, or to the flanking manoeuvres of Li Yuan's cavalry, which had gotten behind the Sui army, the Sui troops collapsed and routed, fleeing back towards Huoyi. Li Yuan's cavalry, however, cut off their retreat. The battle was followed by the capture of weakly defended Huoyi, and the advance on Daxingcheng, which fell to the rebels in November. In the next year, Li Yuan deposed the Sui and proclaimed himself emperor, beginning the Tang dynasty.

During the later reign of the second emperor of the Sui dynasty, Yang, the dynasty's authority began to wane. The main reason was the immense material and human cost of the protracted and fruitless attempts to conquer the Korean kingdom of Goguryeo. Coupled with natural disasters, the conscription of more and more men for the war and the hoarding of scarce grain reserves for the army's needs increased provincial discontent. As a result, from 611 on, rural revolts broke out across the empire, and with the Emperor's prestige and legitimacy diminished by military failure, ambitious provincial magnates were encouraged to challenge his rule. Yang nevertheless continued to be fixated on the Korean campaigns, and only as unrest spread within the empire and the powerful Eastern Turks turned hostile, did he realize the gravity of the situation: in 616, he abandoned the north and withdrew to Jiangdu, where he remained until his assassination in 618.

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