The difficulty of rehabilitation of ancient immigrants in China

At the end of the Northern Song Dynasty, "the difficulty of Jingkang" once again led the people of the Central Plains to move south. Its scale and duration are comparable to the "Yongjia Rebellion" and "Anshi Rebellion" in history. As a result, the population of the south surpassed that of the north for the first time, and the population, economy and culture of China finally moved from the Yellow River basin to the Yangtze River basin. Since then, China society has entered a stage of prosperity in the south and decline in the north.