Un-American Activities (HUAC) began to subpoena artists, producers and screenwriters to investigate communist sympathies in Hollywood. Over the next thirteen years, it came to include Charlie Chaplin, Leonard Bernstein, Dashiell Hammett, Arthur Miller, Paul Robeson, Dorothy Parker, Pete Seeger and Orson Welles.

Ten artists, known as the "Hollywood Ten," originally refused to cooperate with HUAC and were cited for contempt of congress. They were fired and blacklisted by the Motion Picture Association of America the next day in a public announcement. All ten served up to a year in prison, were fined $1,000 and faced great difficulty working in Hollywood again.

In 1950, a pamphlet called "Red Channels" accused 151 actors, writers, directors, musicians and performers of having pre-war connections to left-wing or communist organizations. Those listed were blacklisted from working until they renounced their affiliations and testified to the HUAC. As individuals cooperated and "named names," the list grew. Altogether some 320 people in the entertainment industry were blacklisted for suspected involvement in "subversive" activities.

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