Battle of Jianwei

The Battle of Jianwei was a military conflict over the control of the commanderies of Wudu and Yinping between the states of Shu Han and Cao Wei during the Three Kingdoms period of China. These commanderies were poor and depopulated due to the relocation of resources ordered by Cao Cao years ago. Nevertheless, it was believed that Wudu Commandery still had strategic interest as a foothold for striking into further Cao Wei territory.

The Battle
In 229 AD, Chen Shi, a veteran general of Shu Han, was chosen by Zhuge Liang to lead an army to take Wudu and Yinping commanderies, while the regent himself stayed in the staging area of Yangpingguan as a backup. As soon as Wei military mobilized, Zhuge Liang maneuvered his unit toward Jianwei County, the northwest corner of Wudu commandery. A Wei general, Guo Huai, initially had desired to attack Chen Shi's force, preventing the fall of Wudu and Yinping commanderies, but changed mind when he knew Zhuge Liang had headed toward Jianwei. Avoiding the possibility of being cut off from behind, Guo Huai evacuated the area and drew back, setting up a defensive line behind, preparing for Shu Han's further advance. The Shu regent, on the other hand, chose not to proceed farther after he reached Jianwei. There, Zhuge Liang stationed his troops and anticipated probable Wei reinforcement, which was never sent out; hence the two commanderies soon fell. Deemed as unimportant, the lost of Wudu and Yinping did not incite Cao Wei to reclaim the forfeited lands.

Since Cao Wei had relocated the local tribesmen and livestock away from Wudu and Yinping, continuing to guarding the two commanderies with troops proved to be a futile and strategically useless option - especially in light of the expedition's already-diminished manpower and rations. As a result, Zhuge Liang withdrew the Shu forces from the area, retreating to Hanzhong to construct defenses.

Aftermath
The victory at Jianwei was short-lived, and the manpower and resources invested in it drained the third expedition too greatly; for the rest of 229 and for the first part of 230, the Shu forces could do nothing more than construct a defensive line in Hanzhong in preparation for a Wei offensive towards Hanzhong in the autumn. The diminished Shu forces would launch no further offensives until the fourth expedition in 231.

Despite the strategic unimportance of the two commanderies, the Shu emperor Liu Shan reinstated Zhuge Liang as Chancellor as recognition for the capture of Wudu and Yinping, a title which he had relinquished in the aftermath of the Battle of Jieting.