 Although Swenson had credits on dozens of other television series, including an appearance on the ABC/WB episode "Shady Deal at Sunny Acres" of the western "Maverick", he is best known for his performance as the kindly Lars Hanson in NBC's "Little House on the Prairie".He appeared in forty episodes of the show from 1974–1978.In 1967, Swenson appeared in the western "Hour of the Gun", and played the role of U.S. President Theodore Roosevelt in the western film "Brighty of the Grand Canyon", with co-stars Pat Conway and Joseph Cotten.