Many facts were changed or ignored to add to the feel of the movie. For example, the real George M. Cohan was married twice, and although his second wife's middle name was Mary, she went by her first name, Agnes. In fact, the movie deviated from the truth to such a degree that Cohan's daughter Georgette commented, "That's the kind of life Daddy would have liked to have lived."
This marks the first time a living U.S. President was depicted in a sound film.
The movie's line "My mother thanks you. My father thanks you. My sister thanks you. And I thank you." was voted as the #97 movie quote by the American Film Institute (out of 100).
Walking down the stairs at the White House, James Cagney goes into a tap dance. According to TCM, that was completely ad-libbed.
Despite failing health, the real George M. Cohan acted briefly as a consultant on the film. He lived long enough to see the finished result and approved wholeheartedly of James Cagney's depiction of himself.