He may have not revolutionize acting as his predecessors. But he was very influential to a lot of actors at that time and even after. Dennis Hopper was one of them.
I wouldn't argue his influence at all, just the idea that he revolutionized acting in this country.
Even Brando didn't technically revolutionize anything, he was just the first of his ilk to make the biggest impact, but John Garfield had been around for quite some time before Brando.
The credit would have to go to the Moscow Theater Company created by Stanislavski. They traveled to New York in 1922, and *Maria Ouspsenskaya (of The Wolfman fame) stayed behind to teach the Stanislavski approach. Many of her students were the founders and members of the Group Theater (Lee Strasberg, Stella Alder etc) whose members went on to do their own thing.
Strasberg based on his idea of Stanislavski's teachings created what he called "The Method", Stella Adler a few years later, having gone to Paris to study under Stanislavski himself learned that his teachings had evolved. She took Stanislavski's updated ideas back to New York and began teaching her own classes.
Brando studied under Adler and was somewhat annoyed at being called a method actor because he never learned from Strasberg even though Strasberg tried to take credit. Brando felt Lee became overly concerned about being seen as a great teacher, instead of just being a great teacher (particularly when it came to Marilyn Monroe). But overall he had great respect for Strasberg and his ability particularly because he spawned so many great actors, Dean among them.
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