What other historical events happened on Christmas?

There is virtually no evidence that Jesus of Nazareth was born on December 25th. The date was likely picked for convenience, as it was already celebrated by other major religions as the supposed day of winter solstice. One of these religions was the Roman Sol Invictus cult, officially set up by Roman Emperor Aurelian on December 25th 274 AD. The god is shown on the left of this ancient relief.

The mighty Frankish King Charlemagne united much of Europe under his banner even before being crowned emperor in 800 AD. On Christmas that year, Pope Leo III named him "emperor of the Romans," marking the legendary leader as a successor to ancient Roman caesars. Charlemagne's rule ushered in an age of prosperity and Christian expansion.

Swedish astronomer Anders Celsius officially introduced his Centigrade temperature scale in 1742, but some sources claim he first used it on Christmas Day 1741. Originally, he assigned the value of 0 degrees to boiling water and 100 to the freezing point. This was reversed after his death.

The US civil war ended with the defeat of the southern Confederation in 1865. On December 24th of the same year, a group of confederate veterans met in Tennessee to establish a secret society dubbed the Ku Klux Klan. The infamous organization uses violence in the name of alleged white superiority.

The battlefields of World War I wrought death and destruction, but there were also moments of hope and peace. One such moment is the legendary Christmas truce, which started on Christmas Eve 1914. With Christmas trees popping out along the trench lines in northern France, British and German soldiers sang Christmas carols. On Christmas day, they met to exchange gifts and play a football game.

…and in 1968, the Apollo 8 mission circled the Moon for the first time, making the three US astronauts the first humans to orbit a celestial object. While looking to the Earth across the Moon's surface, the crew read out the beginning of the book of Genesis, in a broadcast watched by millions.

The Soviet Union first deployed its invasion force to Afghanistan on Christmas Day in 1979, with its commandos capturing the radical president Hafizullah Amin in a raid two days later. The events triggered a nine-year war that would end with the Soviet withdrawal.

Early computer networks have been in use since the 1960s, but Christmas day in 1990 marks the first proper test of the system we now know as the World Wide Web. It was developed at CERN as a way to share information among scientists and scholars. On Christmas of 1990, the scientists managed the first successful communication between a Web browser and an Internet server.

For decades, the Soviet Union faced off against the US with diplomatic and military might rivaling resources commanded by Washington. On December 25th, 1991, this came to a close, with the last Soviet leader Mikhail Gorbachev announcing his resignation. The superpower was officially dissolved a day later, with a farewell party set up for the politician.