Count Basie & His Orchestra, led by American jazz pianist and bandleader William "Count" Basie, was a seminal force in the Swing Era of the 1930s and 40s. The orchestra became known for its signature "jumping" beat and intricate brass arrangements, heavily influencing the development of big band music. Notable members included tenor saxophonists Lester Young and Herschel Evans, and singer Jimmy Rushing. Among their most influential works are "One O'Clock Jump" and "April in Paris". Their music represents an essential chapter in the history of American jazz.