Why was Marlon Brando famous?

Answer 1

Brando became famous for his role in A Streetcar Name Desire. His performance in that movie popularized method acting, where a performer immerses themselves in the mindset of their character.

Brando's performance in the movie stands out because every other actor is still using stage acting techniques, clearly annunciating their words and making broad gestures "for the back seats," while Brando plays his role as realistically as possible. He mumbles many of his lines and uses small gestures that a camera picks up, but a stage audience would not have. In doing so he is often credited with revolutionizing acting for film as a distinctly different art than acting for stage.