Because congress adopted a federal holiday on June 26, 1870. Simple.

Why, you ask?

Well, it had an inauspicious beginning in the country. It was so controversial (decadent) in the 1700s that it was actively banned by Puritains, including those who left England to settle the early American states. Perhaps more importantly it was shunned by the Founding Fathers since it was considerd an English tradition and irrelevant to the observance of religion. Alas, Digital History suggests by the early 1800s Christmas in America had become just another famously drunken, lewd and riotous event, rivaling the decadence of old King Charles’ England:

But despite the Puritans’ best efforts, Christmas in America became an excuse for dangerous hell raising. At Christmastime, men drank rum, fired muskets wildly, and costumed themselves in animal pelts or women’s clothes – crossing species and gender. In New York, Philadelphia, Baltimore, and other cities, they formed Callithumpian parades, which involved beating on the kettles, blowing on penny trumpets and tin horns, and setting off firecrackers.

Sounds like a blast, no? Well, the fun obviously never lasts forever and so things eventually came to a head when, according to the History Channel, the effects of Christmas coupled with a rise in poverty and class conflict of the early 19th Century gave concern to those who were in power:

In 1828, the New York city council instituted the city’s first police force in response to a Christmas riot. This catalyzed certain members of the upper classes to begin to change the way Christmas was celebrated in America.

The new message was that people should stay home, sit by a fire, and drink and eat themselves senseless instead of partying outside with others. And so, out of the political discord of 150 years ago we can today say thank you to the federal government for inventing a national tradition and opening the door for America’s two great factions, corporations and religions, to fight over control of the “real” meaning of this holiday.

Thanks should also go to Thomas Nast, arguably the father of modern American political illustration, for creating the modern American image of Santa Claus during the Civil War…it might be worth noting that Santa was always pro-Union and anti-slavery.

Oh, and why December 25th? Apparently Pope Julius I wanted something to compete with the popularity of the festival “Saturnalia”, and probably found it most convenient to just rebrand the pagan holiday with a new name. Merry Saturnalia had a bad ring to it, I guess (especially since the word implied an “inversion of order” instead of something Christ-like).

Personally, I think the holiday should be celebrated on June 26th before someone starts another winter riot over the latest must-have expression of modern faith, like an XBox.