December 25, 2014 04:10 PM

Bing Crosby once joked that a “jackdaw with a cleft palate could have sung it successfully.”

But if it wasn’t for Crosby’s soothing rendition of the Irving Berlin classic, “White Christmas” probably wouldn’t have gone on to become the biggest-selling single worldwide of all time.

In the American Masters documentary Bing Crosby Rediscovered – which debuted earlier this month on PBS but will air again at 9 p.m. ET on Dec. 26 – director Robert Trachtenberg looks back at the indelible mark the song made on both history and the crooner’s legacy.

“Bing had no problem being best known for this song and being so closely associated with Christmas,” Trachtenberg tells PEOPLE. “His feeling was that there was no downside to being tied in with this holiday of love, joy, and good will.”

After performing the tune on his NBC radio show in 1941, Crosby sang “White Christmas” in the 1942 black and white movie, Holiday Inn, opposite actress Marjorie Reynolds. At first, the tune was overshadowed by the flick’s Valentine-themed tune, “Be Careful, It’s My Heart,” but “White Christmas” went on to win an Oscar.

Remarkably, Crosby wasn’t all that impressed with the sentimental tune about having a snowy holiday.

“The first time a worried Irving Berlin played the song for him, Crosby said, ‘Oh Irving, I don’t think you have to worry about that one,’ ” explains Trachtenberg.

And yet 12 years later, the song was featured in the blockbuster hit White Christmas, which featured Crosby singing the songs to soldiers – a scene that actually mirrored what happened in real life.

“When Crosby was singing for the soldiers during WWII he would be asked to sing it, and he said he was sometimes hesitant because it would be so emotional for the men,” Trachtenberg says.

Bing Crosby Rediscovered airs at 9 p.m. ET on Dec. 26. It will also stream on pbs.org/americanmasters beginning Dec. 27.

RELATED: Did Bing Crosby’s Twins Suffer from Fetal Alcohol Syndrome?

You May Like

EDIT POST