Interesting... the "Hollywood Anti-Nazi League":

was founded in Los Angeles in 1936 by Otto Katz and others to organize members of the American film industry to oppose fascism and Nazism. Although it was a communist front organization, run by the American popular front, it attracted broad support in Hollywood from both members and nonmembers of the Communist Party USA (CPUSA). Like many such communist front groups, it ceased all anti-Nazi activities immediately upon the signing of the Molotov–Ribbentrop Pact in August 1939.

Also interesting that they're not listed on Wikipedia's "Anti-fascism" page, which must be heavily patrolled, or that the HANL hasn't been deleted yet for being inconvenient.