Why did the Qing government force people away from China’s coast before conquering Taiwan?

During the 1660s, the Qing government ordered the evacuation of China’s south and southeast coast to cut off support for the anti-Manchu resistance led by Zheng Chenggong (Koxinga) and his successors.12

Zheng Chenggong had utilized bases along the Fujian coast to launch a prolonged campaign against the Qing dynasty. By forcing the coastal population to move inland, the Qing government aimed to isolate these resistance forces, depriving them of supplies, recruits, and communication channels from the mainland. This strategy was part of the broader effort to consolidate Qing control and neutralize the threat posed by the Ming loyalists who eventually retreated to Taiwan.12