Sima Yi

Sima Yi, style name Zhongda, came from Wen county in Henei commandery.

The Jin Shu biography presents Sima Yi as unusually capable and broadly learned from a young age.

The Jin Shu says that amid the late Han disorder Sima Yi often worried about the condition of the realm.

According to the later Jin Shu account, Sima Yi initially declined Cao Cao’s summons by claiming illness; this anecdote is not independently confirmed here.

Cao Cao later summoned Sima Yi into service and assigned him posts in the developing Cao administration.

Sima Yi advised Cao Cao to exploit the opportunity created by Liu Bei’s move into Yi province, but the Jin Shu says the advice was not followed.

After Wei was established as a kingdom, Sima Yi became a close adviser to the heir Cao Pi.

Sima Yi was counted among the “Four Friends” around Cao Pi, along with Chen Qun, Wu Zhi, and Zhu Shuo.

Cao Pi repeatedly entrusted Sima Yi with guarding the capital and supporting the state during military campaigns.

Sima Yi advised Cao Cao not to move the Han court north from Xuchang after the flood crisis, and suggested using Sun Quan’s rivalry with Liu Bei against Guan Yu.

During Zhuge Liang’s northern campaigns, Sima Yi often avoided a decisive battle and waited for conditions to favor Wei.

Sima Yi marched rapidly against Meng Da’s rebellion and reached his city after eight days, before the rebels could coordinate help.

Sima Yi led the campaign against Gongsun Yuan in Liaodong and eventually captured Xiangping after surrounding it.

The Jin Shu account records mass killing after Xiangping fell. This is a grave historical claim that should be described plainly, not softened.

When Cao Rui became gravely ill, Sima Yi was named one of the regents for the young Cao Fang.

Sima Yi seized control in the Gaoping Tombs Incident and removed Cao Shuang’s faction; the coup reshaped Wei politics.

The Gaoping Tombs Incident was a political coup by Sima Yi against Cao Shuang, not a simple transfer of office.

Sima Yi died in 251. The later promotion of his descendants and the Jin dynasty belongs in a historian note.

Cao Cao recruited Sima Yi into public service, beginning a long career within the Cao state.

Sima Yi and Zhuge Liang faced one another during the campaigns around Wuzhang Plains; their rivalry is documented in later histories.

The Jin Shu says that after Zhuge Liang died during their campaign, Sima Yi called him an extraordinary talent. The report concerns an event in Sima Yi’s lifetime, though the exact wording comes from a later source.