Zhang Xingcheng (587 – October 10, 653), courtesy name Deli, posthumously known as Duke Ding of Beiping, was a Chinese official who served as a chancellor during the reigns of the emperors Taizong and Gaozong in the Tang dynasty. Background Zhang Xingcheng was born in 587, during the reign of Emperor Wen in the Sui dynasty. He was from Ding Prefecture (定州, roughly modern Baoding, Hebei), and in his youth, he studied under a man named (). Liu was impressed with his studiousness, and told his other students, "Mr. Zhang does what is proper, and he is material to be an imperial official later." Toward the end of the reign of Emperor Wen's son, Emperor Yang, Zhang was recommended by the officials of his home commandery, and he was made a reserve assistant to the imperial surveyor. After Emperor Yang was killed at Jiangdu (江都, in modern Yangzhou, Jiangsu), in 618 in a coup led by the general Yuwen Huaji, the Sui officials at the eastern capital Luoyang supported Emperor Yang's grandson, Yang Tong (the Prince of Yue), as emperor, but the official Wang Shichong seized the throne in 619, ending Sui and establishing his own state of Zheng. Wang made Zhang his minister of census. During Emperors Gaozu's and Taizong's reigns In 621, Wang Shichong's Zheng state was destroyed by forces from the faction that would later become the Tang dynasty. As Zhang had been a Sui official before, he was made the sheriff of Gushou County (穀熟, in modern Shangqiu, Henan). Later, after he passed an imperial examination, he was made the secretary general of Fuping County (富平, in modern Weinan, Shaanxi), and was considered capable in his position. After his term of office was over, he was made an assistant imperial censor, and was known for willing to submit accusations against other officials for misbehavior notwithstanding their honorable positions. The second Tang emperor, Emperor Taizong, the reigning emperor at the time, was impressed by him, and stated to his chancellor Fang Xuanling, "In both history and current times, officials often came into their offices due to recommendations by others. But I selected Zhang Xincheng myself, without anyone else's recommendations." On one occasion, possibly in 627, when Emperor Taizong, at an imperial feast, began to talk about differences between people from the Guanzhong region and those from the Shandong region (i.e., those from east of modern Sanmenxia, Henan,