It's been 25 years since Mariah Carey's "All I Want for Christmas Is You" debuted, but the iconic Christmas song finally reached the No. 1 spot in the Billboard Hot 100 chart on Dec. 16.
It's also made Carey a lot of money since it was released on her 1994 album, "Merry Christmas" — the song has earned over $60 million in royalties since it was released, according to a 2017 report in the Economist.
Not bad for a song whose famous melody was a "happy accident," said Carey in Amazon Music's recent documentary, "Mariah Carey is Christmas: The Story of 'All I Want for Christmas is You.'"
Carey says she started writing the song while living in upstate New York.
"Actually, I put on [the movie] 'It's A Wonderful Life' downstairs. You could hear it throughout the house," Carey said in the documentary. A self-described "terrible piano player," she started plunking around on an old Casio keyboard.
Carey has said she stumbled upon the melody and chord progression and recorded it on a mini tape recorder.
"It was done very quickly and kind of came out organically, which the best songs do," Carey said in the documentary.
The final song was created by Carey and Walter Afanasieff, a co-writer and producer on the track.
It's true the basic song only took an hour to write, then a week of two of finessing the lyrics, Afanasieff told Billboard.
However, according to Afanasieff, he played the piano as they wrote the original melody together. (A representative for Carey could not be reached for comment.)
Whichever version is true, Carey wasn't originally sold on releasing "All I Want for Christmas Is You." She wasn't sure an original Christmas song from a new artist would resonate with audiences.
"I didn't feel, from a strategic point of view, that it was time to do something like that," Carey told EW in a recent interview. "As much as I love Christmas, I thought that the record company was off. Obviously, I couldn't have been more wrong."
Today, Carey says the song is "one of my greatest achievements," she told Variety in October.
"All I Want for Christmas Is You" is now the highest selling holiday digital song of all time in the United States, with 3.6 million downloads purchased, according to Billboard. On Christmas Eve of 2018 alone, 10.8 million people streamed the track on Spotify.
Its recent place at the top of the Billboard Hot 100 is the first time a Christmas song has been No. 1 since "The Chipmunk Song (Christmas Don't Be Late)" was released in 1958.
As for Cary and Afansieff, though they worked together on several albums, they had a falling out and haven't spoken in 20 years, according to the New York Times.
And while he hasn't made as much money as Carey from "All I Want for Christmas," he told the Times, "I can say that my ex-wives, my children and my grandchildren are enjoying a lot of nice things because of that song."
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