Initially, Walt Disney was uninterested in making this movie. To get him interested, story men Joe Grant and Dick 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?"
Dumbo is the first and only protagonist in a Disney animated feature film to have no spoken dialogue.
A very tightly budgeted, scripted and produced film, because Walt Disney needed it to bring in much-needed revenue after the expensive failures of Pinocchio (1940) and Fantasia (1940). 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 the original grosses of "Pinocchio" and "Fantasia" combined).
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 Gable. The line was also featured in the original theatrical trailer.