Where did communist governments exercise state power and various degrees of influence besides the soviet union, china, and eastern europe during the 20th century?

There were several non-aligned government in Africa and Asia, that in reality were not. In Latin America, Cuba came out strongly as a supporter of communism.

The communist nations used financial and military aid to keep these nations in their sphere of interests. As a result several proxy wars were witnessed.

Social darwinism refers to the the theory that people who succeed in our economic system will one day out compete those who fail. one day the rich will out succeed the poor so we'll that there will eventually be no more poor