According to Rosemary Clooney, the "midnight snack" scene in which Bob Wallace expounds on his theory of what foods cause what dreams was almost entirely improvised.
According to Rosemary Clooney, Bing Crosby and Danny Kaye's "Sisters" performance was not originally in the script. They were clowning around on the set, and director Michael Curtiz thought it was so funny that he decided to film it. In the scene, Crosby's laughs are genuine and unscripted, as he was unable to hold a straight face due to Kaye's comedic dancing. Clooney said the filmmakers had a better take where Crosby didn't laugh, but when they ran them both, people liked the laughing version better.
For the song "Gee, I Wish I Was Back In The Army," there is the lyric, "Jolson, Hope And Benny all for free." This is a reference to three wartime entertainers: Al Jolson, Bob Hope and Jack Benny. The original words were "Crosby, Hope and Jolson all for free," but the lyric was changed because with Bing Crosby in the cast the original lyric would break the fourth wall.
Third of three films to feature Bing Crosby singing "White Christmas." The other two are Holiday Inn (1942) and Blue Skies (1946).
This was the first film photographed in VistaVision. A radical departure from the other widescreen formats of the era, VistaVision did not extend the width of the screen as much as it increased the size of the filmed area of the negative, producing a significantly clearer and sharper image with less lens distortions and more true to life imagery. The hundred or so films shot in VistaVision have been the clearest and most vivid when transferred to high definition home video formats (apart from the 65mm films).