祖大壽
Although forced to retreat, Hong Taiji's forces had nevertheless captured the cities of Luanzhou, Qian'an, Zunhua, and Yongping (present-day Lulong County) during his 1629 expedition. In 1630, he left his cousin Amin in Yongping to defend the newly conquered territory. Zu Dashou embarked on a counterattack and recovered Luanzhou. In response, Amin ordered a massacre of the civilian populations of Qian'an and Yongping, plundering the cities and abandoning them to the Ming. News of the slaughter enraged Hong Taiji, who had been cultivating relations with the Chinese population to pacify captured cities and encourage defection by Ming officers. He had Amin arrested and imprisoned, using the opportunity to appropriate Amin's Bordered Blue Banner army by giving it to Amin's younger brother Jirgalang, who was close to Hong Taiji.