In the history of China, a large number of immigrants were survival immigrants, but after that, there were more and more development immigrants.

In ancient times, the Central Plains was economically developed and occupied a leading position in the country. With every war, people in the Yellow River basin began to migrate to remote areas, most of them moved to the south, but a few moved to the north, especially in the late Tang Dynasty and early Yuan Dynasty. In the former, the Anshi Rebellion lasted until the early years of the Northern Song Dynasty. In order to escape the war, residents in the northern border of the Tang Dynasty began to speak northern dialects.

These people lost advanced production technology and culture, which promoted the feudalization of northern minorities, especially the Qidan nationality, and accelerated the economic development. The essence was Cong Nanhong's migration to the frontier in the early Yuan Dynasty, which formed the climax of the second ethnic integration in China. On the other hand, in order to consolidate the frontier, the feudal government immigrated to the frontier in an organized way. The most representative is that Meng Tian defeated Xiongnu in Qin Dynasty and moved 300,000 households to Hetao area. "Han inherited the Qin system",