of these powers, gongsun shu's chengjia was wealthy and powerful, but gongsun was content to maintain his regional empire and not carry out any military expeditions outside his empire. instead, he sat by as emperor guangwu carried out his unification campaign. emperor guangwu, hesitant to carry out annihilation campaigns, largely preferred first trying to persuade the regional warlords to submit to him. wei and dou did in 29, and as they were assisting eastern han forces to the north of chengjia, gongsun was further discouraged from trying to expand his empire.