Trivia: Most of the secondary cast and extras were people who actually fled Europe to America during Nazi rule. When Laszlo orders the band to play "La Marseillaise," it was very emotional for the cast who sang along and their reactions were very much their true feelings at the time.
Trivia: During production, James Cagney broke a rib whilst filming a dance scene. In spite of the injury, he still managed to complete the sequence.
Trivia: When the wildlife of the forest celebrate the start of a new spring season at the start of the film, a bird feeds her three baby birds a small group of berries that resembles a "Hidden Mickey."
Trivia: Even though Greer Garson plays Richard Ney's mother in the movie, she was only 12 years older than him.
Trivia: In the movie, Lou Gehrig concludes his farewell speech with the famous line "I consider myself the luckiest man on the face of the earth". However, in real life, he continued after this point. The last lines of his speech were "And I might have been given a bad break, but I've got an awful lot to live for. Thank you."
Trivia: The Holiday Inn chain of motels, founded after World War II was named after this movie, not the other way around.
Trivia: A point of interest: The big battle scene at the end of the movie was reused for the beginning of the movie 'The Golden Blade', starring Rock Hudson and Piper Laurie.
Trivia: This is the first film of nine that Spencer and Hepburn appeared together. They fell in love during the shooting of this film.
Trivia: The cartoon reveals for the first time Donald Duck's middle name - Fauntleroy. You can see this on Donald's "Order to Report for Induction" form on the title screen.
Trivia: Henry Daniell, who plays Sir Anthony Lloyd, played several characters in the Basil Rathbone saga, including Professor Moriarty.
Trivia: The opening credits on this cartoon are the artists' actual signatures.
Trivia: Lionel Atwill, who plays Professor James Moriarty, had already played Dr. James Mortimer in the 1939 movie "The Hound of the Baskervilles," with Basil Rathbone and Nigel Bruce.
Trivia: Even though the Ghost of Frankenstein is the title character, he has only two minutes of screen time.
Trivia: Director Alfred Hitchcock has a cameo role in this film - he is seen standing in front of Cut Rate Drugs where Barry Kane is taken upon arrival in New York City.