Incident at Gaoping Tombs

The Incident at Gaoping Tombs (高平陵之變) in 249 was a coup d'état that occurred in the state of Cao Wei during the Three Kingdoms period of Chinese history. The parties involved were Cao Shuang and Sima Yi. Sima Yi seized power during the coup and had Cao Shuang killed. The coup increased the Sima clan's power and influence in Wei, thus providing the foundation of the Jin Dynasty.

In 239, Wei emperor Cao Rui died and was succeeded by the eight-year-old Cao Fang. In his final edict, Cao Rui named General-in-Chief Cao Shuang and Grand Commandant Sima Yi as the regents to assist Cao Fang in ruling Wei. Cao Shuang ostracised Sima Yi and placed his close associates such as He Yan, Deng Yang, Li Sheng (李勝), Bi Gui and Ding Mi (丁謐) in high positions in the Wei imperial court. Cao Shuang promoted Sima Yi to the rank of Grand Tutor, which was actually a move by Cao Shuang to place Sima Yi in a powerless position. Cao Shuang also appointed his brothers Cao Xi and Cao Xun (曹訓) in high military ranks. The imperial guards were also under Cao Shuang's command. Cao Shuang and his associates thus controlled the Wei court. Cao Shuang abused his power by indulging in personal entertainment while neglecting state affairs.

Sima Yi was in a powerless position and was thus unable to participate in discussions on state affairs. In 247, he feigned illness to avoid Cao Shuang and ostensibly retired from public life. The next year, when Li Sheng was sent to Jing Province to assume office as the new Inspector, he paid a visit to Sima Yi before his departure. Sima Yi put up a show in front of Li Sheng and pretended that his health had worsened. Sima Yi pretended to have poor hearing and misheard "Jing Province" as "Bing Province". Later, when a servant came to feed him porridge, Sima Yi pretended to cough so badly that the porridge spilt on his clothes. Li Sheng reported Sima Yi's condition to Cao Shuang and Cao Shuang thought that Sima Yi was going to die soon so he lowered his guard. In the meantime, Sima Yi and his sons Sima Shi and Sima Zhao were secretly preparing for a coup to seize power.

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