Earlier this month, on 7 and 14 January (both Mondays), sounds of merriment could be heard escaping from chalets, dining nooks, and nightclubs in the Saanenland. A quick glance at the Gstaad online events calendar is no help. Confused? Did Monday just become the new Friday? Blame Julius Caesar.

Seriously? Back in 63 BC, Julius Caesar was co-opted Pontifex Maximus, or ‘high priest’ of Rome, a lifetime appointment among the responsibilities of which included properly maintaining the state calendar to ensure sacrifices and rituals occurred on time. By 46 BC, Caesar had been appointed dictator over what was left of the Roman Republic, had no serious opposition anywhere on the horizon, and decided to implement some reforms, the most important of which was fixing the republic’s calendar.

The Roman Republic’s existent 12-month calendar was a hot mess, originally based on lunar observations, with a 355-day year and intercalary months added every four years to try to bring it into alignment with the solar year (365.24217 days, or one trip around the sun). The length and timing of these intercalary months were determined by the pontifex, which meant they were subject to political manipulation: the pontifex could extend the year of ally’s magistracy or shorten that of a rival.

In 46 BC, Caesar’s mathematicians lengthened all 12 months to 30 or 31 days (except February), eliminated the intercalary months, and added ‘leap’ days every four years, resulting in a 365.25-day year (and incidentally lengthening his third year of consulship to 446 days!). Since the Julian year is fractionally larger than the solar year, the new Julian calendar would drift 3 days every four centuries compared to observed equinoxes. By 1582, that drift had grown to 10 days, complicating calculations used to determine Easter, and spurring Pope Gregory XIII to institute the conventional or Gregorian calendar, which we use today.

Though the Gregorian calendar is the most widely used civil calendar in the world, many religious bodies, such as the Eastern Orthodox churches of Russia, Ukraine, Georgia, Macedonia, Jerusalem, and others continue to base their calendars on the Julian system, which in the 21st century runs about 13 days behind the Gregorian calendar. Ergo, Orthodox Christmas is on 7 January  (Gregorian) and Orthodox New Year is on 14 January (Gregorian), also known as the ‘Old New Year’.

In Switzerland, in the reformed protestant canton of Appenzell Ausserrhoden, the Old New Year’s Eve is celebrated on 13 January as Alter Silvester (Old Saint Sylvester’s Day), apparently because the reformed populace had no interest in being told by a pope what calendar to use. The festival, which was first mentioned in 1663 by church authorities who objected to its bawdy character, is marked by Silvesterklaus mummers dressed in elaborate costumes ringing bells and yodelling in a slow manner. Though it was originally thought to be part of the late medieval Advent season, in the 15th century the celebrations became so wild that church authorities moved it to New Year’s Eve.

So, if you’re looking for twice the fun next year, consider emulating the Russians, Appenzeller, et al., and adding a Julian Old New Year to your customary Gregorian New Year’s celebration. And, if you find any quiet time during your extended fête, contemplate pouring one out for good old Julius Caesar, who, after supervising all that hard work, only got to enjoy his new calendar for two more years.

Alex Bertea