Xu Jingzong
Xu Jingzong (592 – September 20, 672), courtesy name Yanzu, posthumously known as Duke Gong of Gaoyang, was a Chinese cartographer, historian, and politician who served as a chancellor in the Tang dynasty. Allied with Emperor Gaozong's powerful wife, Empress Wu (later known as Wu Zetian), Xu Jingzong was exceedingly powerful and effective throughout most of Gaozong's reign. By order of Empress Wu, he played a major role in the elimination of the chancellors opposed to her, between years 657 to 659 and 665. Early life Xu Jingzong was born in 592, during the reign of Emperor Wen in the Sui dynasty. His ancestors had served as officials of the Southern dynasties during the Southern and Northern dynasties period for generations and claimed to be originally from Gaoyang Commandery (, roughly modern Baoding, Hebei) before moving south of the Yangtze River in light of the Jin dynasty's loss of the north. Xu Jingzong's father, Xu Shanxin (), was serving as an emissary of Chen Shubao, the last emperor of the Chen dynasty, to Emperor Wen, whose Sui dynasty then ruled the north, in 589, when Sui destroyed Chen to end the Southern and Northern dynasties period and reunify China. Emperor Wen was impressed with Xu Shanxin's profound sadness (rather than abject submission) at the fall of his state, and made him an official in his own administration. During the Sui dynasty Xu Jingzong himself was said to be knowledgeable of literature in his youth, and, after passing the imperial examination, was made a scribe at Huaiyang Commandery (, roughly modern Zhoukou, Henan). He was soon made a low level official in the imperial administration of Emperor Wen's son, Emperor Yang. In 618, with virtually the entire Sui state engulfed by agrarian rebellions against Emperor Yang's rule, Xu Shanxin and Xu Jingzong were at Jiangdu (in modern Yangzhou, Jiangsu) with Emperor Yang and his other officials, when Emperor Yang was killed in a coup led by the general Yuwen Huaji. Yuwen was initially planning to spare Xu Shanxin, but after Xu Shanxin publicly refused to submit to him by dancing in his presence (then considered a sign of thanksgiving and submission), Yuwen executed him. Xu Jingzong submitted to Yuwen (by dancing) and was spared. His exact travels after Emperor Yang's death were not clear, although it is known that he later served the rebel ruler Li Mi, the Duke of Wei, as a secretary (along with the future Tang chancellor Wei Zheng), before eventually becoming a subject of the Tang dynasty, which emerged victorious from the civil wars near and after the end of Sui. (Sui's last emperor, Emperor Yang's grandson, Yang Tong, posthumously honored Xu Shanxin by posthumously making him the Duke of Gaoyang — a title that Xu Jingzong would eventually receive from Tang.) During Emperor Gaozu's reign It is not clear what Xu Jingzong's activities were initially after becoming a subject of the Tang dynasty under the reign of Emperor Gaozu, but it is known that in 621,