when was the song rudolph the red-nosed reindeer written

The song "Rudolph the Red-Nosed Reindeer" was originally published in a book called "The Legend of Santa Claus" by Robert May in 1939. However, the song was not composed until the late 1940s when the character of Rudolph became popular after the story was adapted into a TV special in 1948. The song was first recorded by Gene Autry in 1949 and has since become a beloved Christmas classic.