Constance Bennett and Myrna Loy, among others, turned the script down. Claudette Colbert only accepted because Capra promised he would double her salary and she would be done in four weeks. She disliked the film so much she didn't even attend the Oscars; when she won for Best Actress she was found about to leave on a trip and was rushed to the ceremony, where she made her acceptance speech in a traveling suit.
Claudette Colbert only wears four different outfits throughout the course of the film: a flimsy nightgown at the beginning, her traveling suit, Clark Gable's pajamas, and her wedding dress.
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. It then became cool to not wear an undershirt which resulted in a large drop in undershirt sales around the country. Legend has it that in response, some underwear manufacturers tried to sue Columbia.
When director Frank Capra asked Claudette Colbert to expose her leg for the hitchhiking scene, she at first refused. Later, after having seen the leg of her body double, she changed her mind insisting that "that is not my leg!"
Columbia Pictures was considered a Poverty Row studio at the time of the film's release. Both MGM and Warner Brothers would lend out temperamental actors to Columbia as a 'humbling experience.' Studio boss Harry Cohn, who was loath to pay for his own roster of contract stars during the early 30's, would invariably assign them to work on Frank Capra's films. Although the studio had received Oscar nominations prior to this picture, its success virtually single-handedly lifted Columbia out of the ranks of poverty row.
The locomotive that holds up Peter Warne, supposedly in New Jersey, is a Southern Pacific 2-6-0 Mogul, number 1662, class M-4, built by the Cooke Works of the American Locomotive Company, commonly known as ALCO.
Clark Gable gave his Oscar for It Happened One Night 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.
She was so convinced that she would lose the Oscar competition in 1935 to write-in nominee Bette Davis, that Claudette Colbert decided not to attend the awards ceremony. When she, contrary to her belief, won that year for her performance in It Happened One Night she was summoned from a train station to pick up her Oscar.
It is widely believed that MGM ensured their contracted star Clark Gable received the Best Actor Oscar to promote his career at the studio. Only three actors were nominated that year, and it was widely believed Charles Laughton would have easily won for his highly acclaimed performance as the tyrannical father in The Barretts of Wimpole Street had he received a nomination.
Several actors in studio records/casting call lists did not appear or were not identifiable in this movie. These were (with their character names): Henry Wadsworth (Drunk Boy), Eddie Kane (Radio Announcer), Charlie Hall (Reporter) and Tom Ricketts (Prissy Old Man).
"Lux Radio Theater" broadcast a 60 minute radio adaptation of the movie on March 20, 1939 with Claudette Colbert and Clark Gable reprising their film roles.
According to Frank Capra, Claudette Colbert was the sixth actress that was offered the lead role. Colbert reluctantly accepted the role turned down by the other five actresses when Capra agreed to double her salary and guarantee that Colbert only had to work for four weeks or less.
Claudette Colbert complained nearly every day during the making of the film. On the last day of shooting, she told a friend "I just finished making the worst picture I've ever made".