The song was first introduced in the 1942 musical Holiday Inn starring Bing Crosby and Fred Astaire. Twelve years later Crosby did a semi-remake of the film - this time with Danny Kaye as his sidekick. I'm sure you are all familiar with the movieWhite Christmas.
Irving Berlin, the composer of the song, had doubts about it but Crosby assured him it was a winner.
It's gone on to become the most performed holiday song in history according to the ASCAP.
There are lyrics to the song that Bing never recorded. They are included below in italics.