Today on the Fab 4 at 4, it's all about the American Influence!

The Beatles' earliest influences include Elvis Presley, Carl Perkins, Little Richard and Chuck Berry. During their co-residency with Little Richard at the Star-Club in Hamburg, from April to May 1962, he advised them on the proper technique for performing his songs.

Of Presley, Lennon said, "Nothing really affected me until I heard Elvis. If there hadn't been Elvis, there would not have been The Beatles."

The Beatles continued to absorb influences long after their initial success, often finding new musical and lyrical avenues by listening to their contemporaries, including Bob Dylan, Frank Zappa and The Beach Boys, whose 1966 album Pet Sounds amazed and inspired McCartney.

Martin stated, "Without Pet Sounds,Sgt. Pepper wouldn't have happened ... Pepper was an attempt to equal Pet Sounds".

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