When was Jesus born? Likely not in December. See Christmas origins – Florida Today

To some people, Christmastime is nothing more than a season of generosity, joy, dressing up evergreen trees, waiting for Santa Claus and buying gifts for their loved ones. To others, it is all of those things, plus a celebration of the birth of Jesus Christ.
But was Jesus actually born in December? And if he wasn’t, why do Christians celebrate his birth on December 25 every year?
Here’s a quick breakdown of the origin of Christmas as we know it, when it’s estimated Jesus might have been born, when Christians started celebrating his birth and where some of our most beloved Christmas traditions come from.
Christmas 2025 will fall on Thursday, Dec. 25.
The exact birthday of Jesus is not known and doesn’t appear in the Christian Bible, but it is estimated that Jesus was born between 6 and 4 B.C., due to the Biblical story of King Herod the Great’s reign, which coincides with the birth of Christ.
As for the actual month and day of Jesus’ birth, there’s no general consensus. The most commonly believed theory estimates Christ’s birth to have been in the spring, based on the Bible’s mention of shepherds tending to their flock, which would have happened only during springtime.
Another theory, based on astronomy, places Jesus’ birth in either the fall of 7 B.C. or the summer of 2 B.C.
According to livescience.com, this theory suggests that “the Star of Bethlehem may have been Venus and Jupiter coming together to form a bright light in the sky, a rare event that occurred in June of 2 B.C. Another possibility is a similar conjunction between Saturn and Jupiter, which occurred in October of 7 B.C.”
The tradition of Christians celebrating Christmas in December came several centuries after Jesus’ death, right after Roman Emperor Constantine converted to Christianity in 312 A.D. The first recorded celebration of Christian Christmas on Dec. 25 was in 336 A.D. under Constantine’s rule.
“Around this time, the Roman Emperor Constantine converted to Christianity. Before this, Romans celebrated Saturnalia, a winter festival, celebrated in late December. Saturnalia involved a week-long feast and celebration. One part of the celebration was giving each other gifts,” The Boston Public Library’s article on the origin of Christmas says.
Some historians believe Constantine chose to celebrate Jesus’ birth near significant dates for pagan traditions to weaken and undermine the significance of these celebrations (Saturnalia on Dec. 17 and Sol Invictus on Dec. 25).
Bad Ancient, a website dedicated to debunking misleading claims about history, says there are likely less malicious reasons that contributed to Constantine’s choice. Those who oppose that theory argue that there are many similarities between the Christian holiday and the pagan holidays that fall near it.
“The incorporation of pagan practices can be detected in late antique Christian sources that describe Jesus as the ‘true Sun’ referring to the birth of the ‘sun’ on the 25th, which applies to both Sol Invictus and Jesus Christ,” Bad Ancient says.
“The view that Christmas was introduced as a reaction to pre-existing pagan practices has been a futile point of view; instead historians such as Martin Wallraff argue that they were ‘parallel phenomena.'”
Santa Claus is inspired by a real monk, named Nicholas, who was born sometime around 280 A.D. near modern-day Turkey, according to History.com.
He was known for generously giving away his inherited wealth and helping the sick and poor. He was admired for his humility, generosity and kindness, and sparked many legends in the centuries following his life.
“Over the course of many years, Nicholas’s popularity spread and he became known as the protector of children and sailors…” History.com says. “By the Renaissance, St. Nicholas was the most popular saint in Europe. Even after the Protestant Reformation, when the veneration of saints began to be discouraged, St. Nicholas maintained a positive reputation, especially in Holland.”
The St. Nicholas version of Santa was first introduced to Americans in the late 18th century, when a group of Dutch families gathered to honor Saint Nicholas’s death date and caught the attention of a New York newspaper.
“The name Santa Claus evolved from Nick’s Dutch nickname, Sinter Klaas, a shortened form of Sint Nikolaas (Dutch for Saint Nicholas),” History.com says. 
“In 1804, John Pintard, a member of the New York Historical Society, distributed woodcuts of St. Nicholas at the society’s annual meeting. The background of the engraving contains now-familiar Santa images including stockings filled with toys and fruit hung over a fireplace.”
As far as dressing up a dead tree with lights, ribbons and ornaments goes – that tradition started in Germany in the Middle Ages. German and other European settlers brought this tradition to America in the early 19th century.
“A New York woodsman named Mark Carr is credited with opening the first U.S. Christmas tree lot in 1851,” History.com says.

source