Horn formed her first trio as a teenager, and recorded her first album, Embers and Ashes, in 1960. Miles Davis heard the album and arranged for her to open for him at New York's Village Vanguard. After making three major-label albums in the mid 1960s, however, Horn largely retired in order to raise her family.
She continued to perform in the Washington, D.C., area, but did not reach a wide audience again until the late 1980s, when she made the first of a series of popular recordings for Verve. Her 1998 tribute to Davis, I Remember Miles, won a Grammy Award.
Last month, Horn was named a National Endowment for the Arts Jazz Master. The award is the nation's highest jazz honor, given to living individuals in recognition of their contributions to the musical form.