Zhu Tao
In 772, after Li Huaixian's successor Zhu Xicai was assassinated, Liu Peng's cousin Zhu Ci (a son of Liu's mother's brother) became military governor. Contrary to the prior independent stand that Li and Zhu Xicai took as to the imperial government, Zhu Ci was more reconciliatory and submissive to the imperial government, and in 774, he went to the Tang capital Chang'an and thereafter served as an imperial general around the capital, leaving his brother (also Liu's cousin) Zhu Tao in actual control of the circuit. Liu served under Zhu Tao, and through his accomplishments was made the commander of the Xiongwu Army (雄武軍, based on modern Chengde, Hebei). Later, he was made the prefect of Zhuo Prefecture (涿州, in modern Baoding, Hebei).