Concentration camp
Cuba, led by Fidel Castro, used concentration camps from 1965 to 1968.  These were forced labor camps for people who Castro thought were bad for Cuba.  Castro's government thought they could "re-educate" these people (change their thinking and behavior) by making them work.  People who were sent to the camps included homosexuals, people without homes or jobs, Jehovah's Witnesses, other religious missionaries, and people who disagreed with the communist government.