Bo, one of the capitals of the
Shang dynasty, lay in what is now Cao . Prior to the
Boxer Rebellion, Cao was an area noted for its lawlessness. When local garrisons were weakened during the
First Sino-Japanese War, a militia known as the
Dadaohui ("Great Sword Company") was set up. It operated until 1895 and may have inspired some of the Boxer Rebellion. ==Administrative divisions==