As the story goes, he was a monk who gave away his hefty inheritance and instead chose to help the poor and the sick.
He's also a patron saint of sailors and was, of course, especially fond of children. (There's one slightly bizarre story, more Halloween than Christmas, of St. Nicholas saving three children who had been "lured into the clutches of an evil butcher.")
He was so popular, according to History.com, that he survived the Protestant Reformation, "when the veneration of saints began to be discouraged."
It wasn't until the 16th century that St. Nicholas began to take on his modern, candy-cane-hued form in images and imaginations. In Europe, he became known as Father Christmas.
He migrated to the Americas with the Dutch, who called him "Sinterklass" and gathered every year on the anniversary of his death. He started making appearances in stores in the 1840s, according to History.com.
The writer Clement Clarke cemented the American image of Santa Claus with his poem "A Visit from St. Nicholas," which begins with the words " 'Twas the night before Christmas."
Now, Santa is all but entrenched in the Christmas lexicon, the rosy-cheeked face of Christmas who is the subject of movies, perennial parental lies and debates about childhood materialism.
There is an annual argument about whether it's okay to portray Santa as only white. There was a Santa photographed last year with a shovel near a fence on the US border with Mexico, a dig at Trump's immigration policies. And there was a Santa who's been called a liar for a story about telling a dying child that he was Santa's "number one elf."
Through it all, the remains of the real-life St. Nicholas were apparently the subject of a centuries-old case of mistaken identity and grave robbery.
According to the Telegraph, St. Nicholas died in AD 343 and was interred at St. Nicholas church in Demre, on the Mediterranean coast of Turkey.
In 1087, apparently, merchants dug up his bones and smuggled them to the Italian city of Bari. It's still a holy site, visited by Christians paying homage to St. Nicholas.
But archaeologists say pilgrims to the Basilica di San Nicola are praying to the wrong guy. The bones belong to another local priest, not one of the most famous saints, the Telegraph reported.
Archaeologists conducting recent surveys at the church in Demre found gaps beneath it. The shrine, they say, is underneath the church and untouched.
"We believe this shrine has not been damaged at all, but it is quite difficult to get to it as there are mosaics on the floor," Cemil Karabayram, the head of Antalya's Monument Authority, told the Turkish Hurriyet Daily News.
Karabayram told the newspaper that he's confident that archaeologists can reach the tomb.
At that point, he believes, nearly 1700 years after St. Nicholas died, he'll give another gift to the people of Demre: Tourism dollars.
