China immigrants in ancient times and China immigrants in modern times.

Population migration is always accompanied by the process of human development. Economy is the main factor affecting population migration, in addition, political, military and religious factors are also important factors affecting population migration. Since the founding of the People's Republic of China, China's population migration is mainly related to economic development. Generally speaking, population migration in China can be divided into three categories:

Population migration in coastal areas, especially the migration from coastal cities to the western region in the 1960s, such as enterprises moving in and going offshore.

2. Urbanization movement characterized by rural labor mobility since the reform and opening up;

3. And engineering immigrants formed by engineering construction projects.

Different from the usual population migration, engineering immigrants are involuntary immigrants. This migration is caused by the construction of reservoirs, transportation, urban infrastructure and other projects. Taking reservoir construction as an example, Xin 'anjiang Reservoir, Sanmenxia Reservoir and Danjiangkou Reservoir built in 1950s and 1960s all produced hundreds of thousands of immigrants. By 2065438+June 2003, the immigrant population of the Three Gorges Project under construction reached one million.

It is estimated that after the founding of the People's Republic of China, the total number of involuntary immigrants formed by engineering construction is more than 40 million. Therefore, involuntary migration has had a great impact on the changes and restructuring of China's social structure.