Warren Douglas was born Warren Douglas Wandberg on July 29, 1911 in Minneapolis, Minnesota, USA. He had one brother, Robert Wandberg, who predeceased him. He was married to Dorothy Kennedy from 1931 to 1957 and had one child, Ann Douglas. He was subsequently married to Eva Lavaughn ("Bonnie") Padgette from 1957 till 1997. He died on November 15, 1997 in Jackson, California, USA.

Warren and Dorothy began their careers as stage actors at the University of Minnesota, moving to New York in the 1930s and going on the road with several plays during the depression. Under contract to Warner Brothers and later Republic Pictures, Warren starred in several films, including The Magnificent Rogue (1946), The Inner Circle (1946), Cuban Fireball (1951), Homicide for Three (1948), The Chinese Ring (1947), and God Is My Co-Pilot (1945). In the 1950s, he wrote screenplays for feature films including Cry Vengeance (1954) and in 1952, he wrote and associate produced the television series, The Files of Jeffrey Jones (1952), starring his old friend Don Haggerty. In the 1960s, he wrote screenplays for the western series' of the time, including Bonanza (1959), Gunsmoke (1955), Sugarfoot (1957), Maverick, Cheyenne (1955), and the feature film, The Night of the Grizzly (1966) with Clint Walker.