What are the main factors of emigrating to the United States?

I think this is a combination of geography and historical knowledge. Historically, most of the first immigrants in the United States were Europeans, that is, Christians. So this is also an important reason why more European Christians immigrated to the past, and their cultural beliefs are the same. Geographically speaking, when the new American continent was discovered, the local natives also had their own religious beliefs, which, together with the beliefs of foreign colonists, constituted a diversified belief concept in the United States. Therefore, American religion is inclusive and suitable for the integration of foreign cultures. Please forgive me if there are any shortcomings.