CNN confirmed the Cotton Club singer's Sunday death, but did not report what caused it.
The Brooklyn, N.Y., native was one of the first African-American artists to sign a long-term movie contract with a major Hollywood studio when she joined MGM in 1942. Her film credits include "Panama Hattie," "Stormy Weather," "Thousands Cheer," "Broadway Rhythm," "Two Girls and a Sailor," "Ziegfeld Follies," "Cabin in the Sky," "Show Boat," "Words and Music," "Death of a Gunfighter" and "The Wiz." She also appeared frequently on TV's "Your Show of Shows" in the 1950s, The New York Times noted.
Although she enjoyed success on stage and as a recording artist, the civil rights advocate frequently said she felt her talents were underused on the big-screen and she was seen as "window dressing" in white movies, CNN said.
"My identity is very clear to me now. I am a black woman," the Times quoted Horne as saying when she was 80. "I'm free. I no longer have to be a 'credit.' I don't have to be a symbol to anybody; I don't have to be a first to anybody. I don't have to be an imitation of a white woman that Hollywood sort of hoped I'd become. I'm me, and I'm like nobody else."
Horne is survived by her daughter, Gail Lumet Buckley.