The Battle of Wuzhang Plains was fought between the contending states of Cao Wei and Shu Han in 234 AD during the Three Kingdoms period of China.

The battle was the fifth and last of a series of Northern Expeditions[3] led by Shu's chancellor, Zhuge Liang, to attack Wei.

He then implemented the tuntian policy to create a new source of food supply, by ordering his troops to grow crops on the south bank of the Wei River alongside the civilians living in the area.

When the other officers disagreed,[10] Guo Huai said, "If Zhuge Liang crosses the Wei River and occupies those plains, his troops will have access to the mountains in the north.

Sima Yi sent Zhou Dang (周當) into position at Yangsui (陽遂; the area north of the Wei River in present-day Mei and Fufeng counties, Shaanxi) and to lure Zhuge Liang to attack him.

Sima Yi said, "Zhuge Liang wants to take control of the Wuzhang Plains and won't advance towards Yangsui.

Several days later, when Guo Huai received news that Zhuge Liang was planning to launch an attack in the west, his subordinates wanted to strengthen the defences in that area.

Zhuge Liang was worried that he could not impose his will due to the lack of reliable supplies, so he divided the army and laid the foundation for a long-term presence.

[18] Meanwhile, Wei emperor Cao Rui ordered Sima Yi to refrain from engaging the enemy and to wait for opportunities to strike.

[19] Zhuge Liang understood that Sima Yi was trying to wear them down through attrition warfare, so he continued the tuntian system to sustain the Shu army.

Sima Yi felt enraged and wanted to attack Zhuge Liang, but Cao Rui denied him permission and ordered him to remain in camp.

Cao Rui even gave Xin Pi his imperial sceptre (a symbol of the emperor's authority) and sent him to the Wuzhang Plains to keep an eye on Sima Yi.

When Zhuge Liang taunted him again, Sima Yi wanted to attack the enemy, but Xin Pi used the authority of the imperial sceptre to order him to remain in camp.

When the Shu emperor Liu Shan heard about it, he sent Li Fu (李福) to the Wuzhang Plains to ask Zhuge Liang about succession.

[26] After a standoff lasting more than 100 days, Sima Yi heard from civilians that Zhuge Liang had died from illness and that the Shu army had burnt their camp and retreated.

Zhuge Liang's assistant, Yang Yi, ordered the Shu soldiers to beat their war drums and get into formation to resist the enemy.

[citation needed] In some variations of this legend, it was Jiang Wei who disguised himself as Zhuge Liang to scare away Sima Yi.

[citation needed] Some days later, Sima Yi surveyed the remains of the Shu camp and retrieved maps, many documents and considerable food supplies.

Xin Pi felt that they could not be certain about Zhuge Liang's death yet, but Sima Yi said, "The most important things for an army are its documents, troops, horses, and supplies.

The ground in the Guanzhong region was full of devil's weed so Sima Yi sent 2,000 men wearing wooden clogs with flat soles to clear the path before his main army advanced.

[29] Wei Yan and Yang Yi separately wrote dispatches to the Shu imperial court and accused each other of treason.

In the meantime, Yang Yi ordered his men to cut down trees to rebuild the gallery roads, and his troops marched day and night to catch up with Wei Yan.

Wang Ping shouted at Wei Yan, "His lordship [Zhuge Liang] had just died and his body had yet to turn cold, and now you dare to do something like this!"

Ma Dai caught up with Wei Yan, decapitated him, brought his head back, and threw it in front of Yang Yi.