The style of R&B began to develop in the beginning of the early 50's. But earlier it was known as rhythm-and-blues. This music has plunged into USA. Rock 'n' roll began to exist in Europe and than worldwide. The basis of rock 'n' roll was rhythm and blues. The founders of R&B were Afro-Americans. The caucasians began to take over the traditions, and with time began to change them. In the fifties, under the influence of Muddy Waters black guitarists, including pianists, made a revolution in rhythm and blues. Read more on Last.fm.