Months before Charlie Chaplin's The Great Dictator reached theaters, The Three Stooges took their own potshots at the posturings of Adolf Hitler in their 1940 short You Nazty Spy! Just how ballsy was this movie in its time? To quote Wikipedia:
The film satirized the Nazis and the Third Reich and helped publicize the Nazi threat in a period when the United States was still neutral about World War II, and isolationist sentiment was prevalent among the public. During this period, isolationist senators such as Burton Wheeler and Gerald Nye objected to Hollywood films on grounds that they were anti-Nazi propaganda vehicles designed to mobilize the American public for war. According to the Internet Movie Database, You Nazty Spy! was the first Hollywood film to spoof Hitler...
The Hays Code discouraged or prohibited many types of political and satirical messages in films, requiring that the history and prominent people of other countries must be portrayed "fairly" [but] short subjects may have been subject to less attention than feature films.
BTW: Both Moe Howard and Larry Fine reportedly cited You Nazty Spy! as their favorite Three Stooges short. No kidding.