Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)

This political satire/black comedy is another Kubrick film that was banned for a pretty random reason. The film deals with an unhinged Air Force general who orders a preemptive nuclear strike on the Soviet Union, and how the rest of the government tries to avoid war. Finland was worried that this satirical look at the Cold War would cause an incident, so they banned it in fear of angering the Soviet Union.