A lifetime member of The Actors Studio, Winfield carved out a diverse career in film, television, theater and voiceovers by taking groundbreaking roles at a time when black actors were rarely even cast. He first appeared in the 1965 Perry Mason episode "The Case of the Runaway Racer" as Mitch, a race car mechanic. His first major feature film role was in the 1969 film The Lost Man starring Sidney Poitier. Winfield became well known to TV audiences when he appeared in several seasons of the groundbreaking television series Julia opposite Diahann Carroll. The show, filmed during a high point of racial tension in the U.S., was unique in featuring a black female as the central character. Winfield also starred as Martin Luther King Jr. in the 1978 miniseries King.
In 1973, Winfield was nominated for the Academy Award for Best Actor for the 1972 film Sounder; his co-star, Cicely Tyson, was nominated for Best Actress. Prior to their nominations and Diana Ross's for Lady Sings the Blues the same year, only three other black Americans – Dorothy Dandridge, Sidney Poitier and James Earl Jones – had ever been nominated for a leading role. Winfield also appeared in a different role in the 2003 Disney-produced TV remake of Sounder directed by Kevin Hooks, his co-star from the original. Winfield played "Jim the Slave" in Huckleberry Finn (1974), a musical based on the Mark Twain novel. Winfield would recall later in his career that as a young actor he had played one of the leads in a local repertory production of Of Mice and Men in whiteface - at the time, a black actor playing the role would have been unthinkable. Winfield also starred in several miniseries, including Scarlett, and two based on the works of novelist Alex Haley: Roots: The Next Generations and Queen: The Story of an American Family.
Winfield gained a new segment of fans for his brief but memorable roles in several science fiction television series and films. He portrayed Starfleet starship Captain Terrell, an unwilling minion of the villain Khan, in Star Trek II: The Wrath of Khan, and Lieutenant Ed Traxler, a friendly but crusty cop partnered with Lance Henriksen in The Terminator. In 1996, he was in the 'name' ensemble cast in Tim Burton's comic homage to 1950s science fiction Mars Attacks!, playing the complacently self-satisfied Lt. General Casey. On the small screen, he appeared in the Star Trek: The Next Generation episode "Darmok" as Dathon, an alien captain who communicates in allegories. He appeared in the second season Babylon 5 episode "Gropos" as General Richard Franklin, the father of regular character Dr. Stephen Franklin, and on the fairy tale sitcom The Charmings as The Evil Queen's wisecracking Magic Mirror. He also portrayed Julian Barlow in the last two seasons of the TV series 227.
Winfield also took on roles as homosexual characters in the films Mike's Murder in 1984 and the 1998 film Relax...It's Just Sex. He found success off-camera due to his unique voice. He provided voices for Spider-Man, The Magic School Bus, Happily Ever After: Fairy Tales for Every Child, Gargoyles, Batman: The Animated Series, Batman Beyond, K10C, and The Simpsons, voicing the Don King parody Lucius Sweet. In his voiceover career, Winfield is perhaps best known as narrator of the A&E true crime series City Confidential from 1998 until his death in 2004.
Throughout his career, Winfield frequently managed to perform in the theater. Checkmates (1988), his only Broadway production, co-starred Ruby Dee and was also the Broadway debut of Denzel Washington. Winfield appeared in productions at the Mark Taper Forum in Los Angeles and The Shakespeare Theatre in Washington, D.C. He was nominated for an Emmy Award for King and Roots: The Next Generations. In 1995, Winfield won an Emmy Award for Outstanding Guest Actor in a Drama Series for his appearance as Judge Harold Nance in the CBS drama Picket Fences.
