Sui conquers the Chen and reunites China

Yang Jian, a Northern Zhou nobleman and father-in-law of Emperor Xuan, became regent in 580 and in 581 took the throne as the first emperor of the Sui. The north had been reunited when the Northern Zhou conquered the Northern Qi in 577, and in 587 the Sui abolished the rump Liang state at Jiangling. In April 588 Emperor Wen denounced the ‘twenty crimes’ of the Chen ruler Chen Shubao and, according to the Zizhi tongjian, had 300,000 copies of the edict spread south of the Yangtze. On 22 November 588 he named three commanders-in-chief: his sons Yang Guang, the future Emperor Yang, and Yang Jun, and Yang Su, who had built a river fleet on the upper Yangtze with five-decked warships holding 800 soldiers each. The chronicle counts 90 area commanders and 518,000 men, all under Yang Guang, on a front from the sea to Sichuan.

The Zizhi tongjian says that more than 100,000 armoured men were still in Jiankang, but Chen Shubao, timid and ignorant of war, left decisions to his favourite Shi Wenqing. On New Year’s Day 589, while he held court in a thick fog, Heruo Bi crossed the river from Guangling, and Han Qinhu with 500 men crossed at night to Caishi, where the garrison was drunk. On 10 February — the date given by the Book of Chen and the Zizhi tongjian; the annals of the Book of Sui give 2 February — the Chen army was routed below the Zhong mountain; the general Ren Zhong went over and led Han Qinhu’s troops through the Zhuque gate, and Chen Shubao, who rejected his minister’s advice to receive the conquerors on his throne ‘as Emperor Wu of Liang had received Hou Jing’, was hauled out of a palace well with two consorts by Han Qinhu’s soldiers. Yang Guang entered the city on 12 February; in late March the Chen emperor and his court were sent to Chang’an, and soon afterwards Lady Xian, the leader of the Lingnan chieftains, brought the far south over to the Sui — in 589 according to the Zizhi tongjian, while the annals of the Book of Sui date the submission of Lingnan to the eighth month of 590.

Emperor Wen became the first ruler since the Western Jin to govern both north and south. The conquest was relatively bloodless: Heruo Bi released his prisoners with food, and Yang Guang sealed the treasuries and archives of the Chen. Although the Sui fell in 618, the unity it restored was preserved by the Tang.