Dalton Trumbo worked as a cub reporter for the Grand Junction Daily Sentinel, covering courts, the high school, the mortuary and civic organizations. He attended the University of Colorado for two years working as a reporter for the Boulder Daily Camera and contributing to the campus humor magazine, the yearbook and the campus newspaper. He got his start working for Vogue magazine. His first published novel, Eclipse, was about a town and its people, written in the social realist style, and drew on his years in Grand Junction. He started writing for movies in 1937; by the 1940s, he was one of Hollywood's highest paid writers for work on such films as Thirty Seconds Over Tokyo (1944), and Our Vines Have Tender Grapes (1945), and Kitty Foyle (1940), for which he was nominated for an Academy Award for Writing Adapted Screenplay.
Trumbo's 1939 anti-war novel, Johnny Got His Gun, won a National Book Award (then known as an American Book Sellers Award) that year. The novel was inspired by an article Trumbo read about a soldier who was horribly disfigured during World War I.
In 1947, Trumbo, along with nine other writers and directors, was called before the House Un-American Activities Committee as an unfriendly witness to testify on the presence of communist influence in Hollywood. Trumbo refused to give information. After conviction for contempt of Congress, he was blacklisted, and in 1950, spent 11 months in prison in the federal penitentiary in Ashland, KY. Once released, he moved to Mexico.
In 1993, Trumbo was awarded the Academy Award posthumously for writing Roman Holiday (1953). The screen credit and award were previously given to Ian McLellan Hunter, who had been acting as a "front" for Trumbo since he had been blacklisted by Hollywood.