After attending Howard University in Washington, D.C., Davis moved to New York City to pursue a career as a writer. He served in the army during World War II but returned to New York City after the war with an interest in acting. In 1946 he made his Broadway debut in Jeb, during the run of which he met Dee, whom he married in 1948.

Davis and Dee frequently appeared together on stage, screen, and television—most notably in Purlie Victorious (1961), a play written by Davis and later adapted for the screen as Gone Are the Days (1963). Davis directed and wrote the films Cotton Comes to Harlem (1970) and Countdown to Kusini (1976). He continued to work into the 21st century, combining his acting pursuits with writing and civil rights campaigning. Davis made several films with Spike Lee (Lee, Spike), including Do the Right Thing (1989) and Malcolm X (1992), in which he reenacted the real-life eulogy he had given for the fallen civil rights leader. Davis also spoke at the funeral of Martin Luther King, Jr. (King, Martin Luther, Jr.), in 1968. The recipients of numerous honours, Davis and Dee were jointly awarded the National Medal of Arts in 1995 and a Kennedy Center Honor in 2004.