Why 250 Million People Celebrate Christmas in January

Christmas is still in full-swing for the 12% of Christians globally who are Orthodox and celebrate the holiday during the first week of January.

Orthodox Christians, who are estimated to number between 250 and 300 million people, hold the same tenets as other Christian denominations, but differ in certain practices, among them being the day they partake in certain holidays. Easter, for instance, is also typically celebrated on a different day because Orthodox Christians elected to follow a distinct calendar after they broke from the Catholic church.

Here’s what to know about why Christmas is celebrated on different dates.

Where did December 25 come from?

Many historians believe that celebrating Christmas in December is tied to the pagan tradition of holding celebrations for the winter solstice, which is around Dec. 21.

This time of year is also tied to the Roman Empire’s custom of celebrating the rebirth of the Sol Invictus, which commemorated a return to days with more hours of sunlight. It’s speculated that religious leaders likely chose to observe Christmas in late December to persuade people to stop celebrating pagan holidays, though others argue that it is because Sextus Julius Africanus, a Roman Christian historian, tied Jesus’ conception to March 25. Nine months after that date would be Dec. 25.

The Roman festival of Saturnalia, celebrating the Roman god Saturn, also falls around Dec. 25. Saturnalia was commemorated by decorating houses with greenery, lights, and the exchange of gifts.

The Roman church officially began celebrating Christmas on Dec. 25 once Christianity became the official religion of the Roman empire and Pope Julius I declared the 25th as the holiday date in the 4th century AD.

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Who celebrates Orthodox Christmas?

The largest number of Orthodox Christians live in eastern and southeastern Europe, including Russia and Ukraine. There are also significant Orthodox Christian populations in the Middle East and in Ethiopia.

Orthodox Christianity is the most common form of Christianity in the Middle East, with most living in Egypt and the Levant. An estimated 10-15 million Egyptians are Christian, the vast majority belonging to the Coptic Orthodox Church.

Is Orthodox Christmas always on Jan. 6?

Orthodox Christmas is typically celebrated on either Jan. 6 or 7. Conflicting Christmas dates trace back centuries, though Pope Gregory XIII sought to solidify a date for the holiday in 1582 when he proposed the Gregorian calendar.

But the Orthodox Church, which split from the Catholic church during the Great Schism of 1054, did not adhere to this proposition. Instead, the National Geographic reports, they relied on the Julian calendar, which means they generally celebrate Christmas on Jan. 7.

Other subsets of Orthodox Christians, like Armenians, celebrate it on the 6th.

However, some Orthodox churches adopted a revised Julian calendar in the early 20th century. Orthodox Christians in Greece, Cyprus, and Romania mark Christmas on Dec. 25.

Why some Christians have wanted to ban Christmas

While Christmas has become a worldwide phenomenon (even celebrated by non-Christians), the holiday was controversial in the church for centuries. Many religious groups did not agree with the holiday’s ties to pagan customs, and sought to renounce Christmas as a whole.

Such was the case with the Puritans, a group of Protestants who sought to cleanse the religion from its ties to Catholicism. They argued that the Bible did not reference the celebration of Christ’s birth, and banned Christmas in 1659 from the Massachusetts Bay Colony, calling it “Foolstide.” (They also famously did not celebrate other holidays like Easter.)

In the 1500s, Scotland underwent similar changes after Catholicism was outlawed following the Reformation of 1560 and the country became Protestant. Scotland banned Christmas in 1640 in an attempt to separate it from Catholic customs, and it did not become a public holiday until 1958.