
Wei supreme commander against Shu northern expeditions.
Cao Zhen was appointed Grand Commander (Da Sima) by Emperor Cao Rui, placing him in charge of all Wei military forces. This appointment made him the highest-ranking military official, responsible for defending against Shu and Wu threats.
Cao Zhen commanded Wei forces against Zhuge Liang's first Northern Expedition. He led a successful defense, repelling Shu attacks and preventing territorial losses. This battle established his reputation as a capable commander against Shu's strategic offensives.
Cao Zhen led a Wei counteroffensive into Shu territory, advancing through the Qinling Mountains. The campaign faced logistical difficulties and was ultimately abandoned due to heavy rains and Shu defenses, resulting in a failed invasion.