What type of cuban gov't did Che guevara overthrow?

And what type of Congolese and Bolivain govt's did Che want to overthrow? I was watching a piece on Che but couldn't get the whole picture of who was who and doing what to who? I know he went to the Congo? but that didn't work out and then he went to Bolivia but the people weren't with him but what was the bolivian gov't doing that Che wanted to overthrow? Was Che a socialist or a communist?