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: Even though Greer Garson plays Richard Ney's mother in the movie, she was only 12 years older than him.
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: 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: Even though the Ghost of Frankenstein is the title character, he has only two minutes of screen time.