He was born in Carman, Manitoba, to Elmer and Elsa Carson. His father was an executive with an insurance company. In 1914, the family moved to Milwaukee, Wisconsin, which he always thought of as his home town. He attended high school at Hartford School, Milwaukee, and St. John's Military Academy, Delafield, but it was at Carleton College that he acquired a taste for acting. Carson became a U.S. citizen in California in 1949.
His success in radio led to the start of a lucrative film career. During the 1930s, as vaudeville declined from increased competition from radio and the movies, Willock and Carson sought work in Hollywood. Carson initially landed bit roles at RKO Radio Pictures in films such as Bringing Up Baby (1938), starring Cary Grant and Katharine Hepburn.
Carson married four times: Elizabeth Lindy (married 1938, divorced 1939), Kay St. Germain (1941–1950), Lola Albright (1952–1958), and Sandra Jolley (1961–1963), former wife of Forrest Tucker and daughter of character actor, I. Stanford Jolley. Carson had a romantic relationship between his second and third marriages with Doris Day in 1950–51, but she left him for Marty Melcher, who would become her third husband.
Radio was another source of employment for the team, starting with a 1938 appearance on the Kraft Music Hall when Bing Crosby hosted the show. In 1942–1943, he was host of The Camel Comedy Caravan, and in the next season he starred in The New Jack Carson Show, which debuted on CBS June 2, 1943. Charles Foster wrote about the show in Once Upon a Time in Paradise: Canadians in the Golden Age of Hollywood: "It broke audience records regularly during the four years it was on the air. Hollywood's biggest stars ... lined up to do guest spots on the show."
Most of his work at Warner Brothers was limited to light comedy work with Morgan, and later Doris Day (who in her autobiography would credit Carson as one of her early Hollywood mentors). Critics generally agree that Carson's best work was in Mildred Pierce (1945), where he played the perpetually scheming Wally Fay opposite Joan Crawford in the title role. Also in 1945, he played the role of Harold Pierson, the second husband of Louise Randall, played by Rosalind Russell, in Roughly Speaking. Another role which won accolades for him was as publicist Matt Libby in A Star is Born (1954). One of his last film roles was as the older brother "Gooper" in Cat on a Hot Tin Roof (1958).
In 1947–1948, he starred in The Sealtest Village Store".
From 1950 to 1951, Carson was one of four alternating weekly hosts of the Wednesday evening NBC Television comedy-variety show Four Star Revue. (The others were veterans Jimmy Durante and Ed Wynn, and up-and-coming young Danny Thomas.) The second season was his last with the show, when it was renamed All Star Revue.
Carson also had his own variety program, The Jack Carson Show on NBC (1954–1955) and was the announcer on the television version of Strike It Rich.
Suspense episodes starring Jack Carson: June 28, 1959 “Analytical Hour” with John Hoyt and Sam Pierce.
On February 8, 1960, Carson received two stars on the Hollywood Walk of Fame for his contributions to the television and radio industry. The television star is located at 1560 Vine Street, the radio star is at 6361 Hollywood Boulevard.
In 1962, while rehearsing the Broadway play Critic's Choice, he collapsed and was subsequently diagnosed with stomach cancer. He died in Encino in 1963, aged 52. Carson was entombed in Glendale's Forest Lawn Memorial Park Cemetery.
Because of his size – 6 ft 2 in (1.9 m) and 220 lb (100 kg), his first stage appearance (in a collegiate production) was as Hercules. In the midst of a performance, he tripped and took half the set with him. A college friend, Dave Willock, thought it was so funny he persuaded Carson to team with him in a vaudeville act – Willock and Carson – and a new career was born with "a very successful comedy team that played large and small vaudeville theatres everywhere in North America". This piece of unplanned Business would be typical of the sorts of things that tended to happen to Carson in many of his film roles. After the act with Willock broke up, Carson teamed with Dancer Betty Alice Lindy for appearances in theaters on the Orpheum Circuit.
