There's a reference to "The Little Engine That Could". While Casey Jr. is trying to get up a hill, the train sounds like it's talking. It says "I think I can, I think I can." Then when the train gets up the hill and starts going faster, it changes to, "I thought I could, I thought I could."
The first Walt DisneyWalt Disney animated feature (and still one of the very few) to be set in America.
Cels for Dumbo are the rarest in the industry. The animators, after the scene was safely "in the can", would strew the used cels in the corridors and go sliding on them. In addition the gray paint (used for so many of the elephant skins) would "pop" when the cel was flexed. Many irreplaceable cels were destroyed this way.
While trying to comfort Dumbo, Timothy says, "Lots of people with big ears are famous!" According to animation historian [?] John Canemaker on the 2001 DVD release commentary, the line was recognized by audiences of 1941 as a reference to Clark GableClark Gable. The line was also featured in the original theatrical trailer.
During production there was a long and bitter animators strike, in which half of the studio's staff walked out. Some of the strikers are caricatured as the clowns who go to "hit the big boss for a raise".
This was Walt DisneyWalt Disney's favorite film made by his studios.
The first Walt DisneyWalt Disney movie for Sterling HollowaySterling Holloway (the Stork) and Verna FeltonVerna Felton (the Elephant Matriarch). Both would become regulars in Disney animated films for the next thirty-five years.
Dumbo and Snow White and the Seven Dwarfs are the only classic Walt DisneyWalt Disney films to use watercolored backgrounds (they were used in this film because they were cheaper than the gouache and oils used for Pinocchio and Bambi) and the last time they were used until Fantasia/2000.
Initially Walt DisneyWalt Disney was uninterested in making this movie. To get him interested, story men Joe GrantJoe Grant and Dick HuemerDick Huemer wrote up the film as installments which they left on Walt's desk every morning. Finally, he ran into the story department saying, "This is great! What happens next?"
The only Walt DisneyWalt Disney animated feature film that has a title character who doesn't speak.
A very tightly budgeted, scripted, and produced film, because Walt DisneyWalt Disney needed the film to bring in much-needed revenue after the expensive failures of Pinocchio and Fantasia. Final negative cost of Dumbo was $813,000 (making it the least expensive of all Disney's animated features), and it grossed over $2.5 million in its original release (more than Pinocchio's and Fantasia's original grosses combined).
Timothy Mouse is a replacement for the robin from the original novel. He was used because elephants are supposed to be afraid of mice.