In the early 20th century, the American music industry used the term "race records" to describe recordings made by and marketed primarily to African American audiences. These records included a variety of genres such as blues, jazz, gospel, and vocal harmony, but they were seldom promoted to white listeners and were often segregated within the industry. By the 1940s, this categorization began to change. As African American popular music evolved, the industry adapted its commercial terminology. In 1949, Billboard retired the “race records” chart and introduced a new category called rhythm and blues.

The term “rhythm and blues” covered a range of musical styles rooted in Black performance traditions. It incorporated elements of swing, blues, boogie-woogie, and gospel, and described the emerging sound of small-band, uptempo music gaining popularity in nightclubs, jukeboxes, and on radio stations. Many early R&B musicians transitioned from the swing era, adapting big band arrangements for smaller ensembles as large orchestras became less common after the war.A defining figure in this transition was Louis Jordan, whose music came to embody a style known as jump blues—a spirited, uptempo blend of swing and blues.

Louis Jordan (1908–1975) was a significant figure in rhythm and blues during the 1940s. Born in Arkansas as the son of a bandleader, he learned to play clarinet and saxophone as a child. Early in his career, he performed with prominent Black musicians such as Charlie “Devil” Gaines, Chick Webb, and briefly, Fats Waller. In 1938, Jordan formed his own group, the Tympany Five, in New York City, where he developed a sound that helped define jump blues and created a link between swing and early rock music.

Jordan’s style included elements such as:

  • Twelve-bar blues forms

  • Boogie woogie bass lines that were often walking and syncopated

  • Shuffle rhythms based on a triplet feel, typically a quarter note followed by an eighth note

  • Group choruses and call-and-response vocals

  • Emphasis on strong backbeats combined with humor in his lyrics and performances

His 1944 song “Is You Is or Is You Ain’t My Baby?” became widely popular and demonstrated his ability to appeal across racial lines. Jordan had a way of incorporating African American folk traditions, language, and cultural references with both humor and respect, making his music meaningful to Black audiences while remaining accessible to white listeners.

Jordan’s biggest commercial success was the 1946 track “Choo Choo Ch’Boogie,” which reached number one on the R&B charts and also performed well on the pop charts. The song features a verse-chorus form and follows a twelve-bar blues structure in each verse. It includes instrumental solos for saxophone and piano that reflect the swing era’s influence. The lyrics describe the postwar experience of Black working-class men dealing with urban life and job challenges.

With its train-themed story, driving rhythm, and clever lyrics, “Choo Choo Ch’Boogie” sold over two million copies and became one of the decade’s top R&B recordings. Other notable hits by Jordan included “Saturday Night Fish Fry” (1949), “G.I. Jive” (1944), “Ain’t Nobody Here But Us Chickens” (1946), and “Let the Good Times Roll.”

Jordan’s music was upbeat and accessible, deeply connected to blues traditions while also appealing across racial and generational lines. His performances were lively, and his records were popular on jukeboxes throughout the 1940s, earning him the nickname "The King of the Jukebox."