This entry from Encyclopedia Britannica features Louis Jordan, an American saxophonist-singer prominent in the 1940s and '50s who was a seminal figure in the development of both rhythm and blues and rock and roll. The bouncing, rhythmic vitality of his music, coupled with clever lyrics and an engaging stage presence, enabled Jordan to become one of the few African-American artists of the 1940s to enjoy crossover popularity with a white audience.