Anne here. Cara/Andrea's post brought us to the end of our Christmastide daily posting and, like many people, we're taking down our decorations (and reindog horns) and going back to our regular schedule. However I just want to slip in one last little sliver of Christmas, because in some traditions the 6th January is the last day of Christmas.
In fact in some parts of the UK, the 6th January is still occasionally called "Old Christmas Day" because for many years it was the day celebrated as Christmas Day.
As with many things, it all started with the Romans. Before the rule of Julius Caesar, calendars were based on the cycles of the moon. Julius Caesar and his astronomers introduced a new, more accurate system based on the sun, and introduced the leap year. (Caesar also named a month after himself – July. Later Augustus did the same thing. Claudius and Nero also tried to have months named after them and while they succeeded for a short time, their months didn't last.)
However the astronomers' calculations were slightly out and they overestimated the length of the year by eleven minutes and sixteen seconds. Over time this built up and by the sixteenth century, the calendar was out by ten days, so in 1582, Pope Gregory XIII deleted the extra days and reformed the calendar. Catholic countries throughout Europe adopted the Gregorian Calendar.
Not, however, Protestant countries, who stuck to the old system rather than follow the edict of a Pope. Finally in 1751 England bowed to common sense and passed the Calendar Act. In order to bring England into line with the rest of Europe, the government simply deleted eleven days in September, and thus the dates went 1st, 2nd, 14th, 15th, etc.
As you can imagine, it was highly controversial, and in some parts of the country people rioted, demanding they have their stolen eleven days returned.
Thus, before this reformation, Christmas Day was celebrated on the equivalent of the Gregorian 6th January, and some, considering it a God-given holy day, and not to be messed about with by foreign popes and governments, continued to celebrate it on the 6th January.
For those in the Eastern Orthodox church, the 6th January, the Feast of Epiphany, when the three wise men are said to have found the newborn Jesus, is a more important date than Christmas. (I couldn't resist including this vintage Australian Christmas stamp on the right.)
In many countries on this day there is a ceremony in which a cross is thrown into the water and the young men dive for it. It's hugely popular in Melbourne, where I live, where it's usually hot, but I recall a snowy winter in the mountains of northern Greece many years ago where they had to break ice in the local river. Brrrr. Luckily it wasn't deep. Guess which of these pictures was taken in Australia and which in Bulgaria.