Why did Zhu Yuanzhang send Nanjing people to the frontier?

Zhu Yuanzhang used immigration policy to consolidate Yunnan frontier.

According to historical records, after Zhu Yuanzhang drove the Mongols back to Mobei, the local government of the Yuan Dynasty was still entrenched in Yunnan. At that time, the supreme ruler of Yunnan was the king of the Yuan Dynasty, and Zhu Yuanzhang sent envoys to Yunnan, hoping that the king would submit to him. At that time, the king listened to Yang's words and killed the envoys who tried to split the country. 138 1 year, Zhu Yuanzhang sent Fu Youde, Mu Ying and Aquamarine to Yunnan with 300,000 troops. Because Qujing, Yunnan is the gateway to Yunnan, King Liang Xiao sent general Darima to guard the Jiang Baishi line of Qujing City, Yunnan Province, and the Ming army crossed the vast Jiang Baishi through the fog at that time (now Jiang Baishi is the stinking ditch of Qujing City, which has lost its former momentum). Yuan army was defeated, Darima died, and King Liang Xiao committed suicide when he heard the news.

Yunnan returned to China after recovery. However, the stability of the frontier is a problem that has long plagued Zhu Yuanzhang. Therefore, Zhu Yuanzhang ordered Mu Ying to lead 300,000 troops to open up wasteland on the spot to defend the border. Those with families also moved to Yunnan to accompany their husbands, while those without families got married on the spot. However, because the Han nationality was not the main ethnic group in Yunnan, Yunnan's economy and society were still in a very backward state. 1383, at Mu Ying's request, Zhu Yuanzhang moved the residents of Nanjing City, as well as the skilled craftsmen in the capital and large families in the south of the Yangtze River at that time, to Yunnan to enrich the frontier. According to historical records, there were more than 2 million soldiers and civilians who immigrated to Yunnan from Jiangsu and Zhejiang in the Ming Dynasty. Today, 2 million people have become 30 million people, and Yunnan has also changed from the wild land of the Ming Dynasty to the south of the plateau.