Charles Mingus Jr. was an American jazz upright bassist, composer, bandleader, pianist, and author. A major proponent of collective improvisation, he is considered to be one of the greatest jazz musicians and composers in history, with a career spanning three decades and collaborations with other jazz greats such as Duke Ellington, Charlie Parker, Max Roach, and Eric Dolphy. Mingus' work ranged from advanced bebop and avant-garde jazz with small and midsize ensembles, to pioneering the post-bop style on seminal recordings like Pithecanthropus Erectus (1956) and Mingus Ah Um (1959), and progressive big band experiments such as The Black Saint and the Sinner Lady (1963).

Charles Parker Jr., nicknamed "Bird" or "Yardbird", was an American jazz saxophonist, band leader, and composer. Parker was a highly influential soloist and leading figure in the development of bebop, a form of jazz characterized by fast tempos, virtuosic technique, and advanced harmonies. He was a virtuoso and introduced revolutionary rhythmic and harmonic ideas into jazz, including rapid passing chords, new variants of altered chords, and chord substitutions. Primarily a player of the alto saxophone, Parker's tone ranged from clean and penetrating to sweet and somber.