Animation in the tone poem "Blue Bayou" was originally created for the deleted "Clair de lune" sequence of Fantasia.
In "Willie the Whale", all of the operatic vocals - bass up through soprano, and even the chorus - were sung by Nelson Eddy.
In the "Casey at the Bat" segment, a sign on the stadium wall announces that the Mudville 9 are playing Burbank in the fateful game, a reference to the location of the Walt Disney studio.
One of Disney's four "Package Films". During the second World War, the studio lost a lot of manpower and resources which left them with countless unfinished ideas too long for shorts, too short for features. So, inventive as they are, they stuck short ideas together into feature length movies. See also The Adventures of Ichabod and Mr. Toad, Melody Time and Fun & Fancy Free.
The "Johnny Fedora and Alice Blue Bonnet" segment was performed by The Andrews Sisters who also performed the "Little Toot" segment in Melody Time.