Battle of Jinyang

Part of Spring and Autumn period

Date	455 BC – May 8, 453 BC
Location	Taiyuan, Shanxi
Result	Zhao victory, Zhi annihilated

Belligerents

House of Zhi
House of Wei (until 453 BC)
House of Han (until 453 BC)

House of Zhao
House of Wei (453 BC)
House of Han (453 BC)

Commanders and leaders

Zhi Yao

Zhao Xiangzi

The Battle of Jinyang (Chinese: 晉陽之戰) was fought between the elite families of the State of Jin, the house of Zhao and the house of Zhi (智), in the Spring and Autumn period of China. The other houses of Wei and Han first participated in the battle in alliance with the Zhi, but later defected to ally with Zhao to annihilate the Zhi house. This event was a catalyst to the Tripartition of Jin in 434 BC, the forming of the three states of Zhao, Wei, and Han, and the start to the Warring States period. It is the first battle described in the Song Dynasty history compendium Zizhi Tongjian.

By 490 BC, after the destruction of the houses of Fan (范) and Zhonghang (中行), control of the State of Jin, then the largest state in China, was contested by four elite families: Zhi, Wei, Zhao, and Han. With multiple military victories under his belt, Zhi Yao (or Zhi Bo Yao 智伯瑤) of the house of Zhi exerted the most influence in the Jin court – all decisions of the state had to pass through him. He also controlled the most territory within the state. The reigning duke of Jin, Duke Ai, was powerless to restrain him. So Zhi Yao, in his pride, began to demand lands from the other three houses. The houses of Wei and Han reluctantly complied to evade Zhi's wrath, but Zhao Xiangzi (趙襄子) refused to cede the territories of Lin (藺) and Gaolang (皋狼), both in modern-day Lishi, to Zhi. Zhi, in retribution, formed a secret alliance with the houses of Wei and Han to attack Zhao.

Zhao Xiangzi suspected an attack from Zhi, since he has heard that Zhi sent envoys to Han and Wei three times, but never to Zhao. After rejecting suggestions to move to Zhangzi or Handan out of concern for the people there, Zhao Xiangzi asked his minister Zhang Mengtan (張孟談) where he could prepare his defence, and Zhang Mengtan suggested Jinyang because Jinyang had been well-governed for generations. Zhao agreed, and summoned Yanling Sheng (延陵生) to lead the army carriages and cavalry ahead to Jinyang, Zhao himself to follow later. Once in Jinyang, Zhao Xiangzi, following the suggestions of Zhang Mengtan, issued orders to refill the granaries and the treasuries, repair walls, make arrows, and melt copper pillars for metal. By virtue of past governance, the treasuries, granaries, and arsenals were filled within three days, and the walls repaired within five. Thus all of Jinyang was prepared for war.

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Wikipedia