During WWII, the British used Monopoly games to help POWs escape.

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Monopoly has been beloved for generations, but the history of the classic board game isn’t all fun and games. During World War II, specially manufactured Monopoly boards were used to help prisoners of war escape from captivity. In 1940, the British government struck a deal with Waddingtons, the company that manufactured London-themed editions of Monopoly, in which MI9, a secret department of the War Office, tasked Waddingtons with creating a version of Monopoly that contained various tools and information to aid POWs in their potential escape efforts.