Taishan Commandery was created in 122 BC, when the king of Jibei offered the land surrounding Mount Tai to the Han emperor.
[1] In late Western Han dynasty, the commandery administered 24 counties: Fenggao (奉高), Bo (博), Cha (茬), Lu (盧), Feicheng (肥成), Yiqiu (蛇丘), Gang (剛), Chai (柴), Gai (蓋), Liangfu (梁父), Dongpingyang (東平陽), Nanwuyang (南武陽), Laiwu (萊蕪), Juping (鉅平), Ying (嬴), Mu (牟), Mengyin (蒙陰), Hua (華), Ningyang (寧陽), Chengqiu (乘丘), Fuyang (富陽), Taoshan (桃山), Taoxiang (桃鄉), Shi (式).
[3] In 140, Taishan covered 12 counties, including Fenggao, Bo, Liangfu, Juping, Cha, Laiwu, Gai, Nanwuyang, Nancheng (南城, formerly part of Donghai Commandery), Fei (費, formerly part of Donghai) and Mu.
[4] After Jin reunification, Taishan administered 11 counties in 280, namely Fenggao, Bo, Ying, Nancheng, Liangfu, Shanchi (山茌, formerly Cha), Xintai (新泰, formerly Pingyang), Nanwuyang, Laiwu, Mu and Juping, with a total population of 9,300 households.
In Northern Wei, 6 counties, Juping, Fenggao, Boping, Ying, Mu and Liangfu, were in the commandery, with a total population of 91,673 in 26,800 households.