Sima Zhao

Sima Zhao (pronunciation^ⓘ) (211 – 6 September 265), courtesy name Zishang, was a Chinese military general, politician, and regent of the state of Cao Wei during the Three Kingdoms period of China and Emperor of Jin dynasty

Sima Zhao capably maintained control of Wei, which had been seized by his father Sima Yi and previously maintained by his older brother Sima Shi, successfully crushing all internal opposition in the form of dissent and rebellion. In 263, despite opposition, he decided to take advantage of the present weakness in Shu Han to the west and launched an invasion against it, which eventually managed to convince its emperor, Liu Shan, towards formally surrendering, tipping the decades-long established balance of power decisively in Wei's favor. Towards the end of the campaign, he had himself created the Duke of Jin and accepted the Nine bestowments—a step that put him closer to usurpation of the throne—although he never actually ascended the throne, having further styled himself the King of Jin in 264, and then died in 265. His military credit and successful grip on the political scene helped to set up the plot of overthrowing Wei by his son, Sima Yan, who usurped the Wei throne and proclaimed the Jin dynasty with himself as its emperor in 266. After the establishment of Jin, Sima Yan posthumously honoured his father as Emperor Wen of Jin (晉文帝), with the temple name of Taizu (太祖).

A Chinese idiom involving and inspired by Sima Zhao states that "Everyone on the street knows what's in Sima Zhao's mind" (司馬昭之心, 路人皆知), meaning that a person's supposed hidden intention (in this case, usurping the throne) is so well known that it is not really hidden. It came from a quotation by Cao Mao, fourth emperor of Wei, who launched an unsuccessful uprising against Sima Zhao in an attempt to take back imperial power.