Late in 1927, Ellington's orchestra landed a job as the house band at Harlem's most prominent nightspot, the Cotton Club. The engagement would prove extremely productive for Ellington. He continued to seek out musicians with distinct, even unusual, instrumental voices; he composed a variety of music to accompany the acts and honed his sense of pacing and showmanship. The three-year engagement at the club, along with records and radio broadcasts, made him a national figure.

The Ellington orchestra made about 200 recordings during its Cotton Club years, and grew from ten to twelve players, offering Ellington more challenges and opportunities for composing. His now-famous "jungle music," a kind of musical exotica, originated during this period.