|This article needs additional citations for verification. (January 2011)|
|Regent of Cao Wei|
|Died||255 (aged 46–47)|
|Style name||Ziyuan (子元)|
|Temple name||Shizong (世宗)|
Sima Shi (208–255), style name Ziyuan, was a military general and regent of Cao Wei during the Three Kingdoms era of Chinese history. In 249, he assisted his father Sima Yi in overthrowing the emperor Cao Fang's regent Cao Shuang, allowing the Sima family to become paramount authority in the state, and he inherited his father's authority after his father's death in 251. He maintained a tight grip on the political scene and, when the emperor Cao Fang considered action against him in 254, he had Cao Fang deposed and replaced with his cousin Cao Mao. This tight grip eventually allowed him to, at the time of his death in 255, transition his power to his younger brother Sima Zhao, whose son Sima Yan eventually usurped the throne and established the Jin Dynasty.
After Sima Yan became emperor, he, recognizing Sima Shi's role in his own imperial status, posthumously honored his uncle as the Emperor Jing of Jin (晉景帝), with the temple name Shizong (世宗).
Career up to 251
It is not known when Sima Shi was born, but it is known that he was Sima Yi's oldest son, born of Sima Yi's wife, Lady Zhang Chunhua (張春華). When he was young, he was known for the elegance in his conduct and his intelligence. As his father was an important Wei official, Sima Shi himself climbed up the ranks of officials fairly rapidly.
When Sima Yi planned a coup d'état against Cao Shuang in late 248; according to Jin Shu, Sima Yi confided only in Sima Shi, with even his younger brother Sima Zhao excluded from the discussion (although Sima Guang found this unlikely and, in his Zizhi Tongjian, opined that Sima Yi planned the coup with both Sima Shi and Sima Zhao). Sima Shi put together a group of 3,000 loyal men without knowledge by Cao Shuang or his associates, and when Sima Yi set to carry out his plans in 249, Sima Shi was able to quickly summon the men to carry out the coup.
Once Sima Yi overthrew Cao Shuang and replaced Cao as regent for the emperor Cao Fang, he rewarded his son with the title the Marquess of Changpingxiang. Sima Shi became his father's assistant, although there was no particular record of his accomplishments during these years. After Sima Yi died in 251, he took over his father's positions without significant opposition—after his father had, earlier that year, suppressed a failed rebellion by Wang Ling (王淩) and massacred the clans of Wang and his associates.
During Cao Fang's reign
Sima Shi was a capable politician and administrator, but he also quickly wanted to prove his military reputation. In 252, he made a major attack against Eastern Wu, whose founding emperor Sun Quan had recently died and whose current emperor, Sun Liang, was under the regency of Zhuge Ke. Zhuge Ke was able to deal Sima Shi's forces a major blow, but Sima Shi maintained himself well by making humble admissions of faults to the public and promoting the generals who tried to stop his campaign. In 253, after Sima Shi defeated Zhuge Ke in a major battle, his reputation was established, while Zhuge Ke's own was undermined (due to Zhuge Ke's failure to admit fault), and Zhuge soon fell while Sima's power was affirmed.
In 254, Sima Shi made a violent move to consolidate his power, at Cao Fang's expense. Cao Fang had endeared himself to the minister Li Feng (李豐), and there had been suspicious by Sima Shi that they were plotting against him. He summoned and interrogated Li Feng, and when Li refused to disclose his conversations with the emperor, Sima Shi beat him to death with a sword handle and then accused Li Feng and his friends Xiahou Xuan (夏侯玄) and Zhang Ji (張緝) of treason, and had them and their families executed. Cao Fang was further forced to depose of his wife Empress Zhang, who was Zhang Ji's daughter. These moves further terrorized the officials into submission.
Cao Fang was very angry about the deaths of Li Feng and Zhang Ji, and later in 254, his associates submitted a plan to him—that when Sima Shi's brother Sima Zhao would arrive at the palace for an official visit before heading to his defense post at Chang'an, to kill Sima Zhao and seize his troops, and then use those troops to attack Sima Shi. Cao Fang was apprehensive and paralyzed, and did not implement the plan, but news was still leaked to Sima Shi. Sima Shi then forced Cao Fang to step down, although Sima spared his life and gave him his old title of the Prince of Qi. When Sima Shi notified Cao Fang's stepmother Empress Dowager Guo that he intended to make Cao Pi's brother Cao Ju (曹據), the Prince of Pengcheng, emperor, however, she managed to persuade him that such a succession would be improper—that since Cao Ju was the uncle of her husband Cao Rui, such a succession would leave Cao Rui effectively sonless with no heir. Sima Shi was forced to agree with her, and he made, as she suggested, Cao Mao emperor instead. (Cao Mao, although 13 years old at the time, was known for his intelligence, and Empress Dowager Guo might have believed that he, alone of the princes and dukes, might have had a chance of counteracting the Simas.)
During Cao Mao's reign
Despite Empress Dowager Guo's intentions and Cao Mao's own intelligence, they made very little impact in trying to stem the tide of the Simas' growing power. In reaction to the removal of Cao Fang, in 255, the general Wuqiu Jian, the commander in the important eastern city of Shouchun (壽春, in modern Lu'an, Anhui), along with another general Wen Qin (文欽), raised a rebellion against the Simas, but were quickly crushed by Sima Shi's army. Wuqiu Jian was killed, and his clan was slaughtered. Wen Qin and his sons fled to Eastern Wu.
The campaign had its tolls on Sima Shi, however. He was ill with an eye disorder at the time that Wuqiu Jian and Wen Qin's rebellion started, and had just had an eye surgery. He was initially therefore reluctant to lead the forces himself and wanted his uncle Sima Fu to lead the forces against Wuqiu Jian and Wen Qin. At the urging of Zhong Hui and Fu Gu (傅嘏), he led the troops himself, which was important in the victory against Wuqiu Jian, but during one of the raids made by Wen Qin's son Wen Yang (文鴦), Sima Shi, in his anxiety, aggravated the eye that he had just had the operation in—causing his eye to pop out—and his conditions soon deteriorated greatly. Less than a month after he put down the rebellion, he died while at Xuchang (許昌, in modern Xuchang, Henan), with his brother Sima Zhao in attendance to succeed him.