Hong Chengchou
In June 1641, Hong Chengchou and Wu Sangui returned to Songshan and garrisoned the northwest area. Prince Zheng Jirgalang attacked several times towards Songshan and Xinshan but was defeated repeatedly, the Ming army succeeding in surrounding the Qing army four times. Though the Qing army finally broke through the encirclement, their casualties were very high. Due to Wu Sangui's bravery, the Ming army remained on the offensive, but it also paid a heavy price.