It is the winter solstice today, celebrated in Rome as part of Saturnalia.
Fans of Net Zero design with their underperforming solar panels won't be celebrating this shortest day of the year, but we have noted previously that for many, the winter solstice is a time of celebration;
In the northern hemisphere, knowing when the dark days of winter would start to lengthen could give hope to people trying to make the harvest of the previous year stave off starvation for a few more months. The day was so important, that some of humanity's earliest monumental structures were aligned with the rising or setting of the sun on the winter solstice. Stonehenge in England, for example, is lined up with the winter solstice.
The Christmas tree is part of the celebration of the solstice and the longer Roman holiday of Saturnalia. According to History.com,
Early Romans marked the solstice with a feast called the Saturnalia in honor of Saturn, the god of agriculture. The Romans knew that the solstice meant that soon farms and orchards would be green and fruitful. To mark the occasion, they decorated their homes and temples with evergreen boughs. In Northern Europe the mysterious Druids, the priests of the ancient Celts, also decorated their temples with evergreen boughs as a symbol of everlasting life. The fierce Vikings in Scandinavia thought that evergreens were the special plant of the sun god, Balder.
With the rise of Christianity, this celebration of the sun god became déclassé until the Protestant Reformation, when trees became popular in Germany. But not in America, where they were considered by the Puritans to be pagan. That is why it is so odd that Making Christmas Great Again is such a thing; it was basically illegal until the tradition was brought from Europe by immigrants.
In 1659, the General Court of Massachusetts enacted a law making any observance of December 25 (other than a church service) a penal offense; people were fined for hanging decorations. That stern solemnity continued until the 19th century, when the influx of German and Irish immigrants undermined the Puritan legacy.
TreeHugger Christine has described how in Germany, the yule log is a big deal, especially when living in an old stone house:
We love the hours spent poking into the flames and relaxing, dreaming of the joyous fire the yule log will create. We look forward to the house filling with people, and anticipate the warmth that will envelop us when we occupy enough rooms to justify turning on the heating instead of huddling about the fire place or a space heater.
These days, with our worries about particulates from burning wood, we might look askance at burning big logs in big inefficient open fireplaces. As TreeHuggers we should probably be not be cutting down trees simply for the purpose of decorating our homes for a few days. But really, they are a celebration of life and light and longer days ahead. For the sun worshippers among us,
Many ancient people believed that the sun was a god and that winter came every year because the sun god had become sick and weak. They celebrated the solstice because it meant that at last the sun god would begin to get well. Evergreen boughs reminded them of all the green plants that would grow again when the sun god was strong and summer would return.
That is worth celebrating.