Tian Chengsi

Tian Chengsi (田承嗣) (705 – March 4, 779), formally the Prince of Yanmen (雁門王), was a general of the Chinese rebel state Yan, who later submitted to and became a general of Tang Dynasty, from which Yan had rebelled. As was in the case of several other Yan generals who submitted to Tang but who had substantial army and territorial holdings, Tian was allowed to retain his command and territory, semi-independent of the Tang imperial government structure, and among these generals, he was particularly defiant of the Tang imperial government.

Tian Chengsi was born in 705, during the reign of Emperor Zhongzong of Tang. His family was from Ping Prefecture (平州, roughly modern Qinhuangdao, Hebei), and his ancestors, for several generations, had served in the military. His grandfather Tian Jing (田璟) and father Tian Shouyi (田守義) both had reputations for upholding justice in the region. Late in the reign of Emperor Zhongzong's nephew Emperor Xuanzong, Tian Chengsi served as a forward commanding officer under the general An Lushan, the military governor (jiedushi) of Fanyang Circuit (范陽, headquartered in modern Beijing), and particularly impressed An with his ability to maintain strict military discipline. For his contributions in campaigns against the Khitan and the Xi tribes, he was promoted several times, eventually to be a general under An.

An Lushan rebelled against Emperor Xuanzong's rule in late 755 and, on his campaign south to attack the Tang eastern capital Luoyang, had Tian, along with An Zhongzhi and Zhang Xiaozhong, serve as his forward commanders. An's forces quickly captured Luoyang, and he declared himself the emperor of a new state of Yan there. In 757, after An Lushan had been assassinated and succeeded by his son An Qingxu, Tian continued to serve under An Qingxu and commanded a campaign to capture the key Tang city of Nanyang (南陽, in modern Nanyang, Henan) and then to attack south further, but while he trapped the Tang commander Lu Jiong (魯炅) in Nanyang, he was not able to capture the city quickly, and after Lu eventually fought his way out of the siege and fled to Xiangyang, Tian abandoned the campaign as well and returned to Luoyang.

...
Wikipedia