Favoring native populations over immigrants is known as

Favoring the interests of native-born people over foreign-born people or immigrants is called nativism.

Nativism is defined as the political policy that promotes the interests of native inhabitants compared to those of foreign-born people or immigrants. Nevertheless, immigration restriction position is currently its most common description.
Some people think nativism is a negative term and they prefer to call themselves patriots.

to stay where they were until m sent for