Baxi Commandery (巴西郡) was a commandery in northern Yi Province, covering the hilly country north-east of Chengdu around modern Nanchong and Langzhong in Sichuan. Its position between the Sichuan Basin and Hanzhong made it strategically important as a buffer and staging area during campaigns along the Hanshui and upper Jialing rivers.
During Liu Zhang’s rule Baxi was part of the eastern shield of Yi Province. When Liu Bei advanced into Yi, control of Baxi and neighbouring commanderies became crucial for stabilising the northern frontier. Later, in the struggle between Shu Han and Cao Wei, Baxi and the surrounding region formed the theatre for the Battle of Baxi and related operations as each side sought to threaten or defend the Hanzhong corridor.
The scholar-official Qiao Zhou is recorded as coming from Xichong in Baxi, illustrating the commandery’s role not only as a battlefield but also as a home for learned figures in Shu Han.