Guillaume was best known for the Benson character, which he played on the '70s sitcom Soap and on his own spin-off Benson. Benson started as a butler and worked his way up to lieutenant governor. Guillaume won Emmys for both shows, first for supporting comedy actor on Soap in 1979 and then for lead comedy actor for Benson in 1985. He was the first black actor to win Lead Actor in a Comedy Series.
He also voiced Rafiki in The Lion King and played managing editor Isaac Jaffe on Aaron Sorkin's sitcom Sports Night. He had an eponymous sitcom in 1989 that lasted for one season. He also made memorable guest appearances on shows including All in the Family, Good Times, The Jeffersons and The Fresh Prince of Bel-Air. He won a Grammy for Best Spoken Word Album for Children in 1995 for a Lion King companion book.
Guillaume was also an accomplished stage actor, earning a Tony nomination for best actor in a musical in 1977 for playing Nathan Detroit in a revival of Guys and Dolls.
He was born Robert Williams in St. Louis on Nov. 30, 1927. He served in the Army before beginning his acting career. He made his Broadway debut in 1961 in Kwamina.
He is survived by his wife Donna Brown Guillaume and a son and a daughter; a son, Jacques, died in 1990.