Starting from the Supervisory State of Nanming

On March 18, the seventeenth year of Chongzhen in the Ming Dynasty (AD 1644), Li Zicheng captured Beijing. The next day, Emperor Chongzhen Zhu Youjian hanged himself on Meishan in the imperial city. The Ming Dynasty regime in Beijing fell. Subsequently, the Qing army entered the customs, but at this time, half of the Ming Dynasty still existed in the south. On May 15th of the same year, King Fu Zhu Yousong proclaimed himself emperor in Nanjing, with the reign name Hongguang, and the Hongguang regime was established. In May of the following year, the Qing army went south to capture Yangzhou, and then Nanjing fell. Emperor Hongguang was captured and taken to Beijing for execution, and the Hongguang regime was destroyed. Let's see how the protagonist can turn the tide against collapse and support the building from collapse under this historical background.