Cao Mao’s death during his campaign against Sima Zhao

Cao Mao’s death during his campaign against Sima Zhao is the moment when resistance to Sima Zhao’s control of Wei becomes an open confrontation—and the emperor is killed in the street. Cao Mao sets out with a small palace force to challenge the man whose power has eclipsed the throne; Jia Chong orders Cheng Ji to kill him. The aftermath makes the political imbalance unmistakable: Sima Zhao controls the response, Cheng Ji and his family bear the announced punishment, and another distant relative of Cao Cao is placed on the throne.

Causes and Political Background

The confrontation follows a poem that profoundly angers Sima Zhao. He takes it as evidence that Cao Mao wants to meet the same fate as Cao Fang and concludes that the emperor must be removed. Jia Chong offers to carry out the task. The poem’s effect thus exceeds literary insult: it prompts a decision at the centre of power and brings the existing struggle between emperor and regent into the open.

In the summer of 260, Sima Zhao goes to the palace. Cao Mao rises to greet him, and the courtiers call for Sima Zhao to receive the highest honours. When Cao Mao does not respond, Sima Zhao rebukes him, invoking his family’s service to Wei across three generations. He then confronts Cao Mao over the poem’s image of a dragon in a well, interpreting it as a disrespectful depiction of his own family. Cao Mao says nothing, and Sima Zhao leaves after imposing a chill on the court. The scene shows a ruler who still occupies the throne but cannot freely answer the man who commands the political room around him.

The Emperor’s Appeal and Departure

In despair, Cao Mao withdraws to his inner chambers and summons Wang Shen, Wang Jing, and Wang Ye. He tells them that Sima Zhao intends to seize the throne and asks them to help overthrow him. Wang Jing argues that Sima Zhao has secured the important appointments and that no one at court can challenge him; he advises Cao Mao to live with the situation. Wang Shen and Wang Ye, concerned for their families, decide to report the conversation to Sima Zhao. Wang Jing alone refuses. Their divided response leaves the emperor with neither a viable court coalition nor secrecy about his intentions.

Cao Mao nevertheless summons his guards and a crowd of roughly three hundred servants, takes his sword, and leaves the palace in the imperial carriage. Wang Jing weeps and prostrates himself, warning that the small group cannot fight Sima Zhao and is like sheep entering a tiger’s mouth. Cao Mao refuses to turn back. His procession is soon confronted in the street by Jia Chong on horseback, Cheng Ji and Cheng Zu, and thousands of armed troops. Cao Mao asserts that he is the Son of Heaven and asks whether they intend to murder their rightful ruler. The appeal states the central conflict plainly: the emperor claims legitimate authority, while the armed force before him answers to Sima Zhao.

The Killing and Its Immediate Aftermath

Jia Chong turns to Cheng Ji and identifies the reason Sima Zhao has retained him. Cheng Ji asks whether Cao Mao is to be killed or taken prisoner; Jia Chong answers that he is to die, by order of Sima Zhao. Cao Mao calls Cheng Ji a traitor, but Cheng Ji kills him. The emperor’s guards flee. Wang Jing alone cries out in protest and is seized and bound as a report is sent to Sima Zhao. The abrupt collapse of the procession contrasts the imperial title and carriage with the actual power of the troops surrounding them.

When Sima Zhao arrives, he pretends to be deeply upset. He later asks the court officials how the perpetrators should be punished. Chen Tai, dressed in mourning, calls for Jia Chong’s death as a partial apology to the country. Sima Zhao asks whether a lesser punishment is possible. Chen Tai instead identifies Cheng Ji as the real traitor and calls for his execution and the destruction of his clan. Cheng Ji protests that he only followed Jia Chong’s instructions, but Sima Zhao has his tongue cut out and orders Cheng Ji and Cheng Zu publicly executed, along with the rest of their family. The official response punishes the men who carried out the killing while leaving Sima Zhao, whose order Jia Chong relayed, at the centre of power.

Blame, Succession, and Political Consequences

A poem that follows the killings makes the distinction between the punished agent and the presumed author explicit: Sima Zhao ordered Jia Chong to kill the emperor, while Cheng Ji and his clan paid for the crime. Wang Jing and his entire family are also executed. His earlier refusal to betray Cao Mao’s appeal offers no protection once the court’s response is controlled by Sima Zhao.

After Cao Mao’s formal burial, Sima Zhao selects Cao Huan, a distant relative of Cao Cao, to take the throne, and the account declares Sima Zhao back on top. The succession does not restore an independent emperor; it confirms that Sima Zhao can determine who occupies the throne after the reigning emperor has been killed. When news reaches the Shu court, Jiang Wei argues that regicide in Wei legitimizes an invasion against those responsible. He writes to Wu seeking its participation and again sets out for the Qishan hills. Cao Mao’s failed resistance therefore has consequences beyond the palace: it becomes a political justification for renewed military action against Wei.