Clark Gable gave the Oscar he won for his performance in this movie to a child who admired it, telling him it was the winning of the statue that had mattered, not owning it. The child returned the Oscar to the Gable family after Clark's death.
It Happened One Night (1934) became the first film to perform a "clean sweep" of the top five Academy Award categories, known as the Oscar "grand slam": Best Picture, Best Director, Best Actor, Best Actress, and Best Screenplay. This feat would later be duplicated by One Flew Over the Cuckoo's Nest (1975) in 1976 and The Silence of the Lambs (1991) in 1992. However, It Happened One Night is the only one not nominated in any other category.
Columbia did not have much faith in the film and released it without much fanfare and little advertising. It was quickly pushed out to secondary theaters where it suddenly became a runaway success, and eventually became Columbia's biggest hit to date.
When director Frank Capra asked Claudette Colbert to expose her leg for the hitchhiking scene, she initially refused. Later, after having seen the leg of her body double, she changed her mind, insisting that "that is not my leg!"
While shooting the scene where he undresses, Clark Gable had trouble removing his undershirt while keeping his humorous flow going and took too long. As a result, the undershirt was abandoned altogether. An urban legend follows that it then became cool to not wear an undershirt, which supposedly resulted in a large drop in undershirt sales around the country. Legend also has it that in response, some underwear manufacturers tried to sue Columbia.
Frank Capra: as one of the passengers on the bus singing the third couplet of "The Daring Young Man on the Flying Trapeze".