Modern actors are more likely to cause scandal with their actions — say, an inappropriate message or drunken rant — than by their political views. In the late 1940s and through the ’50s, that dynamic was reversed: America was on high alert for Communist infiltrators, and Hollywood, the traditional bastion of the left, became one of the centers of investigation. The Screen Actors Guild was, after all, a union and since its founding was allied with AFL-CIO, one of the biggest unions and suspected socialist organizations in America.

On this day, November 17, in 1947, just days before its delegates were scheduled to testify before the House Committee on Un-American Activities, the Screen Actors Guild voted to force its officers to take a “non-communist” pledge.

Hollywood studios were no friends of communism, but they also vehemently resented HUAC’s intrusion into their operations. At the same time, understanding a full investigation would certainly cut into their business, they issued a statement promising to keep “proven communists” away from anything that might go on to the screens. This was not good enough, however, as the House Committee issued subpoenas to several dozen actors and filmmakers. Some were willing to cooperate, others attempted to answer the Committee questions in their own way, which only got them labeled as subversives