Many countries seem to use local people to recruit soldiers when colonizing another country. Why do they use local people? It seems that colonial riots in history were all caused by local people

Let me try to explain my understanding. My understanding is that there are probably the following three factors that determine how colonialism mostly recruits local indigenous people as soldiers:

First, employing people cost. The nationals of our own country who are recruited to serve as soldiers must have higher requirements than the locals in the colonies. Whether it is wages, benefits or welfare policies, they will do whatever they want because they have control over the colonies.

Second, there are many secrets that cannot be revealed and need to be kept. Because generally speaking, colonies are geographically far away from so-called civilized societies, and information is relatively unavailable. The colonists do not want the outside world to know many of their measures and activities, such as many bloody massacres, cruel exploitation, etc., and they still have to survive in the world. To maintain the image of an advanced empire in front of us. Therefore, generally speaking, "civilized" countries, including their own citizens, are rarely hired as mercenaries. The local indigenous people have no such concerns.

Third, local indigenous people are easy to rule. Comparatively speaking, the local indigenous people's thoughts were enlightened relatively late, and they did not form the kind of strong cohesion for national restoration or independence. If a large number of nationals are requisitioned, problems will easily arise. The best example is North America's independence. In North America, colonial countries such as the United Kingdom, Spain and France adopted genocidal policies, and then requisitioned a large number of their own citizens and immigrated to develop. Finally, North America became independent, and the United States later became the world's dominant power.

Therefore, generally speaking, imperialism will not conscript its own citizens as soldiers at an older age.

Instead, we use local people with "high quality and low price"