Edgar Bergen was one of the most popular ventriloquists of the 1940s even having his own radio show featuring Charlie McCarthy and Mortimer Snerd. After seeing this film he said he was dismayed to see how much he moved his lips, blaming it on the fact that on radio he did not have to not move his lips and had become spoiled.
While the film is often credited as the last time Walt Disney voiced Mickey Mouse, this is inaccurate. It was indeed the last film to feature Disney's voice, as he recorded much of Mickey's dialogue in the spring and summer of 1941. But later, Disney recorded some lines as Mickey Mouse for the television show Le Club Mickey (1955).
The song "Fun and Fancy Free (I'm a Happy-Go-Lucky Fellow)" as sung by Jiminy Cricket was intended to be used in Pinocchio (1940) but was dropped.
In Mickey et le haricot magique (1947), it is never explained where Mickey gets the beans from. One draft featured Honest John Foulfellow, the villainous fox from Pinocchio (1940) as a swindler who sold Mickey the magic beans. Another version had Mickey giving the cow to the Queen of Happy Valley (played by Minnie Mouse) in exchange for them.
This is one of the first Walt Disney films to list the voice credits for the animated characters, and the first to list Mickey Mouse, Donald Duck and Goofy as if they were actors in a live-action film.