Final answer:
Approximately 500 people from Hollywood were blacklisted for suspected Communist ties during Red Scare II, orchestrated by HUAC to prevent the spread of Communist ideology through film. This led to severe career repercussions for many artists and influenced Hollywood's production of anti-Communist films.
Step-by-step explanation:
During the period of the Red Scare II, the House Committee on Un-American Activities (HUAC) targeted the Hollywood film industry, fearing the spread of Communist ideas through movies. In September 1947, 43 subpoenas were issued to industry members, leading to the Hollywood Ten who refused to cooperate. Subsequently, over three hundred individuals were placed on a blacklist, including actors, writers, directors, and musicians. It's estimated that approximately 500 people from Hollywood were blacklisted for being suspected Communists or having Communist affiliations. This action by Hollywood executives and the HUAC was an attempt to eliminate any subversive influence within the film industry.