Tian Ji'an (781 or 782[a] – September 21, 812),[3] courtesy name Kui and formally the Prince of Yanmen, was a general of the Tang dynasty, who, as military governor (jiedushi), ruled Weibo Circuit (魏博, headquartered in modern Handan, Hebei) in a de facto independent manner from the imperial regime.
[4] In 806, Tian Ji'an was further given the honorary chancellor designation of Tong Zhongshu Menxia Pingzhangshi (同中書門下平章事).
Emperor Xianzong finally agreed after Wang Chengzong agreed to allow two of Chengde's prefectures, De (德州, in modern Dezhou, Shandong) and Di (棣州, in modern Binzhou, Shandong) be separated into a different circuit under imperial control, to be named Baoxin Circuit (保信, to be headquartered at De Prefecture).
He made Xue Changchao (薛昌朝) the prefect of De Prefecture, whose wife was from the Wang clan, the military governor of the new circuit.
[9] Emperor Xianzong thereafter ordered a campaign against Chengde, and with the main imperial forces—the Shence Army (神策軍), commanded by the eunuch Tutu Chengcui—set to arrive in Weibo's vicinity, Tian was summoning his officers to discuss how to react—fearing that if the imperial forces were successful against Chengde, Weibo would be next.
Tian agreed with Tan, and in a pre-arranged attack captured Chengde's Tangyang County (堂陽, in modern Xingtai, Hebei).