Tang China (618–907 ce) suffered a continuing crisis from the mid-eighth century. On the one hand, control over the whole empire by the central government, based at the capital Chang’an 長安, weakened as a consequence of the An Lushan Rebellion (755–763); on the other, the powers of provincial governors increased in reaction. Among the semi-autonomous provinces, Weibo 魏博 was one of three located in Hebei 河北 (the region north of the Yellow River 黃河) and notorious for causing trouble for the court. From the establishment of Weibo Province in 763 until 820, it had been under the control of the Tian 田 family. Over a span of nearly sixty years, five members of the family were “appointed” as governor of Weibo: Tian Chengsi 田承嗣 (in office 763–779), Tian Yue 田悅 (in office 779–784), Tian Xu 田緒 (in office 784–796), Tian Ji’an 田季安 (in office 796–812), and Tian Hongzheng 田弘正 (previously named Tian Xing 田興, in office 812–820). Officially they were appointed by the Tang court, but in reality each had already become governor before approval from Chang’an arrived, and the Tang court merely acknowledged their positions. This was one of the main characteristics of the semi-autonomous provinces in the middle and late Tang: their governors needed acknowledgment from the Tang court, yet the court could not determine who should be the governor.

Among these five governors from the Tian family, only Tian Hongzheng chose to obey imperial orders, while the other four challenged court authority at times and even launched rebellions. Indeed, Tian Chengsi had been a general in An Lushan's rebel army who surrendered to the Tang court in 763 and was thus rewarded with command of Weibo Province. Tian Yue was his nephew, and Tian Xu was his son. Tian Ji’an was Tian Xu's son, thus the grandson of Tian Chengsi. These four had a relatively close relationship and shared a political outlook. Their disloyalty came to be recorded and criticized in biographies compiled by court historians and much later included in Tang official histories. By contrast, Tian Hongzheng was only a distant relative of the other four, a second cousin of Tian Xu. He had been at the periphery of the ruling family before he became the governor by accident.