American jazz drummer who was known for his role in the development of free jazz beginning in the 1960s.

Blackwell played with rhythm-and-blues groups in New Orleans, where he was influenced by the city's musical tradition and by such drummers as Paul Barbarin. From 1951 Blackwell lived in Los Angeles and performed with saxophonist Ornette Coleman (Coleman, Ornette), before moving to New York City in 1960 to become the regular drummer in Coleman's quartet, which was at the forefront of the free jazz movement. Blackwell also performed with a number of other avant-garde musicians, including trumpeter Don Cherry and a group headed by trumpeter Booker Little and saxophonist Eric Dolphy. In 1975 he became artist in residence at Wesleyan University, Middletown, Conn. From 1976 he performed and recorded with other former Coleman associates under the name Old and New Dreams.