Karl Swenson (July 23 1908 – October 8 1978) was an American theatre radio, film, and television actor.

Born in Brooklyn, New York, Swenson made several appearances on Broadway in the 1930s and 40s, including the title role in Arthur Miller's first production, The Man Who Had All the Luck. He appeared extensively on the radio from the 1930s through the 1950s in such programs as Cavalcade of America, The Chase, Columbia Presents Corwin, The Columbia Workshop, Inner Sanctum Mysteries, Joe Palooka, Lawyer Q, Lorenzo Jones, The March of Time, The Mercury Theatre on the Air, Mrs. Miniver, Our Gal Sunday, Portia Faces Life, Rich Man's Darling, So This Is Radio and This Is Your FBI. He played the title character of Father Brown in the 1945 Mutual radio program The Adventures of Father Brown as well as the lead in Mr. Chameleon.

Swenson entered the film industry in 1943 with two wartime documentary shorts, December 7th and The Sikorsky Helicopter, followed by more than thirty-five roles in feature films and television movies. No Name on the Bullet (1959) is only one of the many Westerns he did for both film and television.

Although Swenson had credits on dozens of TV series, including an appearance on the "Shady Deal at Sunny Acres" episode of Maverick, he was best known for his performance as Lars Hanson in forty episodes of Little House on the Prairie. Swenson died of a heart attack in Torrington, Connecticut, ironically shortly after filming the episode in which Hanson died.

Of Swedish descent, burly, light-haired character actor Karl Swenson was born in Brooklyn and started his four-decade career on radio. Throughout the late 30s and 40s, his voice could be heard all over the airwaves, appearing in scores of daytime serials ("Lorenzo Jones") and mystery dramas ("Inner Sanctum Mysteries"). He gave visual life to one of his serial characters, Walter Manning, in "Portia Faces Life" when it went to TV in 1953. It was during his lengthy work in this medium that he met his wife, stage and radio actress Joan Tompkins. They appeared together throughout their careers on TV and in a few films. In the 1950s, he kept afloat on TV in rugged guest spots ("Dr. Kildare" (1961), "Gunsmoke" (1955), "Maverick" (1957), "Mission: Impossible" (1966) and "Hawaii Five-O" (1968)). He didn't appear in films until age 50+ with minor roles in Kings Go Forth (1958), North to Alaska (1960), Birds, The (1963) and Sons of Katie Elder, The (1965). His voice was also well utilized in such animated features as Sword in the Stone, The (1963) as the voice of Merlin. Karl met actor Michael Landon on the set of "Bonanza" (1959), appearing in four separate episodes over time. Landon remembered him when he began to film "Little House on the Prairie" (1974). Cast in the recurring role of lumber mill owner Lars Hanson, he remained with the show until his death in 1978 of a heart attack. His character on the show also died.