meaning: Restoring peace by force") as a favour for him, and a stone slab celebrating his deed was erected by the court in the city. Zhang Shicheng occupied Xuzhou as the northernmost city of his domain in 1360. The Ming forces under Xu Da , captured Xuzhou in 1366. Soon Köke Temür sent an army under General Li Er to attack Xuzhou. Fu Youde () and Lu Ju () who held the city raided them outside, most of the enemy were drowned while the remained about 270 soldiers and 500 horses were captured. Xuzhou had a long period of prosperity during the Ming dynasty. The flourishness largely attributed to the carriage, especially by the Grand Canal, one of seven customs barriers (or customs houses, ) under the Ministry of Revenue was located in Xuzhou. It was retained until the late Qing. Korean Choe Bu affirmed that the city where he travelled by way of, hardly pale by comparison to the Jiangnan region. As a hub for both the national courier system and the grain tribute system for several centuries, Xuzhou was of vital importance. Thus, the government of Ming established three garrison areas namely guards in the present-day area: Xuzhou guard (), Xuzhou Left guard () and Pizhou guard () for its security. Yet, the local navigation was considerably constrained by two Rapids: the Xuzhou Rapids (), a kilometer southeast of the city, and the Lüliang Rapids (), another 24 kilometers further south. The remedy provided by the Ministry of Works is constructing the Jia Canal, which paralleled the treacherous stretch of Xuzhou. However, the canal completed in the 1600s ravaged the city. Not only it disrupted the former drainage system, but also depressed the local economy. Prior to the recession, flooding and the famines followed struck Xuzhou frequently. The worst flooding occurred in 1624: it was immersed up to 1 zhang and 3 chi (about 4m) within the city. After the Hongguang Emperor enthroned in Nanjing, the court designated four defense areas along the southern bank of the Yellow River () to repulse the Qing armies. While the former bandit general, Gao Jie () was designated to take the crucial forward position at Xuzhou by Shi Kefa. But the assassination of Gao seriously reduced the court's capacity to deal with challenges from Qing. Gao's successor was Li Chengdong (). Being aware of forthcoming attack, Li deserted Xuzhou in the