Answer:
The Beatles were influenced by many musicians through out their life, directly and indirectly.
In John's earlier life he was influenced by Elvis Presley and adopted his look and rock and roll attitude.
In the early sixties John met Bob Dylan which moulded the future of his songs and his attitude towards drugs.
George Harrison was influenced by he Byrds, and most importanly Ravi Shankar who showed George Indian music. (which led to George's playing of the sitar and the production of many famous beatle songs with the sitar, ie Norweigan wood)