Christmas is all about joy, togetherness, and festivities, with plenty of activities to share with friends and family. Decorating the Christmas tree, waiting for Santa, exchanging gifts, watching holiday specials, and enjoying hearty meals are all part of the fun. But technically, it’s a celebration of Jesus’s birthday. So, where did all these other traditions come from?

The exact origins of modern Christmas celebrations, as they are known in the U.S., are difficult to pinpoint. However, there are some clues about their cultural beginnings. According to Kyle Smith, a professor of the history of religions at the University of Toronto Mississauga, many of the significant changes in how Christmas is celebrated emerged in the second half of the 19th century.

Much of it has to do with the traditions passed down by settlers from the Netherlands who arrived in America in the 17th century. “Dutch immigrants to the United States, specifically to New York, are really important for the history of Christmas,” says Smith.

At that time, Christmas was outlawed in the English colonies where Puritans held power. They opposed the holiday because it wasn’t mentioned in the Bible and viewed it as an excuse for debauchery. However, in the Dutch-controlled New Netherland colony, including cities like New Amsterdam (modern-day New York), there were no such strict prohibitions.

The Dutch observed Christ’s birth in their own way, calling it Kerstydt, but this celebration was often overshadowed by a more popular December tradition: Sinterklaas. This Dutch gift-giving holiday involved children placing their shoes outside their homes to be filled with treats by St. Nicholas on December 6th.

In 1624, New Netherland’s population was just 270 people, with few, if any, children. But over the following decades, dozens of families settled in the outpost, bringing their traditions with them. As the number of Dutch residents grew and eventually outnumbered others, their customs became the most widespread and influential in the area.

Sinterklaas eventually evolved into Santa Claus among English-speaking communities. His popularity grew as stories and images of the Dutch figure spread through literature. At the same time, writers like Washington Irving and Clement Clark Moore in the United States (‘Twas the Night Before Christmas) and Charles Dickens in England (A Christmas Carol), along with numerous other authors and illustrators, played a significant role in shaping Christmas into the more modern, commercialized celebration we know today.

Moore’s stories introduced the idea of Santa as an elf with a sleigh pulled by reindeer, delivering gifts by coming down chimneys. Meanwhile, Dickens’ works, particularly A Christmas Carol, shifted the focus of Christmas celebrations toward children’s gifts and family feasts at home.

Santa Claus, as we know him today, first appeared in Harper’s Magazine in 1863 through an illustration by Thomas Nast. He was depicted as a plump elf with a beard, a hat, and, of course, as a generous gift-giver. “It’s completely fair to claim that Santa Claus is an American invention,” Smith says.

The origin of the Christmas tree is also somewhat mysterious. According to Smith, there’s a long history of people across Europe bringing greenery into their homes during the cold winter months and decorating it.

The modern Christmas tree, however, traces back to 19th-century Germany. That’s why it’s typically a fir or pine tree, and almost never something like a palm tree. Even so, the exact origins are hard to trace. “There’s no aha moment to say, ‘Oh that’s a Christmas tree,’” Smith explains.

And if you weren’t already aware, December 25th isn’t actually Jesus’s birthday. The date came about from the winter solstice festivities held by the Romans. “We have no idea when Jesus was born,” says Smith. There are no textual records specifying the year, month, day, or even season of his birth.

While the winter solstice now falls on December 21st, it was celebrated on December 25th before Julius Caesar reformed the Roman calendar in 44 BCE. Later, in 325 CE, the First Council of Nicaea officially decreed December 25th as Christmas, aligning it with existing solstice celebrations like the pagan Feast of the Unconquered Sun.

Still, the idea of Jesus being born on December 25th stuck. “The most compelling theory is the whole point of the idea of the Messiah coming into the world at its darkest hour,” Smith says.