Li Zhengji
When Emperor Dezong came to the throne, there were four major circuits that were ruled by their military governors in effectively independent manner from the imperial government—Pinglu (平盧, headquartered in modern Tai'an, Shandong), governed by Li Zhengji; Weibo (魏博, headquartered in modern Handan, Hebei), governed by Tian Yue; Chengde (成德, headquartered in modern Shijiazhuang, Hebei), governed by Li Baochen; and Shannan East (山南東道, headquartered in modern Xiangfan, Hubei), governed by Liang Chongyi. The four circuits were allied with each other, and their governors intended to pass the control of the circuits within the family. In 781, when Li Baochen died, Emperor Dezong, wanting to show imperial authority, refused to let his son Li Weiyue inherit the circuit. The four circuits thus prepared for war against the imperial government. (Li Zhengji also died later in the year, and similarly, Emperor Dezong refused to let his son Li Na inherit the circuit.)