After auditioning and landing a stage role in the touring company of Porgy and Bess in 1949 on the great contralto Etta Moten’s suggestion, he went on tour with the opera, where the opera’s statesman as Porgy, William Warfield, commended his performances and requested that Peters be his understudy. It was during this time while he was touring in Europe with the opera that the celebrated African American actor-singer-activist Paul Robeson saw him in his career-defining role as “Crown” and purportedly declared that he was “a young Paul Robeson”.

Peters made his film debut in Carmen Jones in 1954, but began to make a name for himself in such films as To Kill a Mockingbird and The L-Shaped Room. He received a Tony nomination for his starring stint in Broadway’s Lost in the Stars.

Peters sang background vocals on the 1956 hit “Day-O” by Harry Belafonte, as well as on Belafonte’s 1957 hit, “Mama Look at Bubu”. He led the chorus at recording sessions for Belafonte’s iconic 1956 album Calypso. He also sang on the song “Where” from Randy Weston’s 1959 album Live at the Five Spot and shared vocal duties with Martha Flowers on Weston’s album of the following year, Uhuru Afrika. During this time, Peters and Belafonte became close friends, sharing similar political views and approaches to their careers. In 1963, he played Matthew Robinson in Heavens Above!, a British satirical-comedy film starring Peter Sellers, directed by John and Roy Boulting. He played a supporting role as the gangster Rodriguez in the 1964 film, The Pawnbroker, one of the first confirmed homosexual characters in an American film. He played “Jesse” in a 1972 episode of Gunsmoke. He was a special guest star in the third season of The Streets of San Francisco, playing the character “Jacob” in the episode called “Jacob’s Boy” (1974).

In the film Abe Lincoln, Freedom Fighter (1978), Peters plays Henry, a freed black slave who is falsely accused of robbery but, defended by Abraham Lincoln, is found not guilty due to the fact he has a damaged hand and could not have committed the crime. In To Kill a Mockingbird, Peters plays Tom Robinson, a black man falsely accused of raping a white girl, whom Atticus Finch shows could not have committed because his hand (and arm) were damaged. In 1970 Peters portrayed the voice of African-American boxer Jack Johnson in Bill Cayton’s film of the same name, and it is in this role that he can be heard at the end of Miles Davis’ soundtrack album, Jack Johnson, saying: “I’m Jack Johnson. Heavyweight champion of the world. I’m black. They never let me forget it. I’m black all right! I’ll never let them forget it!”

Between 1981 and 1996, Peters provided the voice of Darth Vader for the radio adaptations of the first three Star Wars films for National Public Radio. He also played the role of a Colonial prosecutor trying to make a murder case against Starbuck in an episode of the original Battlestar Galactica.

Peters was once romantically involved with actress Ja’net Dubois. Peters was married to Dolores ‘DiDi’ Daniels from 1961 until her death in 1989. Their daughter Lisa Jo Peters was born November 3, 1962. Peters delivered the eulogy at Gregory Peck’s funeral in 2003. His character, Tom Robinson, was defended by Peck’s Atticus Finch in 1962’s To Kill a Mockingbird. He died in Los Angeles of pancreatic cancer on August 23, 2005, at the age of 78. Peters is buried in the Revelation section at Hollywood Hills Forest Lawn Cemetery, in Los Angeles, CA.

He was involved in many community projects, including being chairman of the Dance Theatre of Harlem, and was awarded the 26th Screen Actors Guild Achievement Award in 1990 for career achievement and humanitarian contributions.

He appeared in the films Star Trek IV: The Voyage Home and Star Trek VI: The Undiscovered Country as Fleet Admiral Cartwright of Starfleet Command. Peters portrayed Joseph Sisko, father of Deep Space Nine’s commanding officer, Benjamin Sisko, on Star Trek: Deep Space Nine. In 1993, he was a member of the jury at the 43rd Berlin International Film Festival. In early 2005, six months before his death, Peters guest-starred in an episode of JAG during its final season, “Bridging the Gulf”, season 10 episode 15. Peters worked with Charlton Heston on several theater productions in the 1940s and 1950s. The two became friends and subsequently worked together on several films, including Major Dundee, Soylent Green, and Two-Minute Warning. He voiced Lucius Fox in several episodes of Batman: The Animated Series and Morris Grant/Soul Power in the animated series Static Shock (2000–2004).