This is the first in a two-part series.

Column: Pothole Prairie, by Tim Engstrom

As you know, most of the world counts the years based on when Jesus Christ was born — at least by rough estimates. That is where we get the number for A.D. 2014.

So with Christmas Day and New Year’s Day upon us, let’s talk about calendars today and next Tuesday.

The Western world uses a 12-month calendar called the Gregorian calendar. It is named for Pope Gregory XIII, for in 1582 he refined what had been the Julian calendar by correcting the length of the year so that the spring equinox would fall closer to its fixed date of March 21. It had drifted earlier in the calendar by 10 days over the centuries, which threw off the preferred time of year for Easter Sunday. Upon the advice of advisers, Gregory dropped 10 days in the calendar so it would line up with the seasons. In 1852, the calendar went from Oct. 4 to Oct. 15. Gregory decreed that leap days would not occur in years divisible by 100 — unless they also were divisible by 400.

In other words, we had a leap day in 2000, but we won’t have one in 2100, 2200 and 2300.

Catholic countries adopted the Gregorian calendar immediately, but Orthodox and Protestant countries were less willing. For instance, the British Empire didn’t adopt it until 1752, and by then it needed to skip 11 days to catch up. When America purchased Alaska from Russia, we had to switch it from the Julian calendar to the Gregorian calendar. In 1867, Alaskans went from Oct. 6 to Oct. 18. Plus, we repeated the day of the week so that “tomorrow” — or what eventually became the International Date Line — switched to the western side of Alaska from the eastern side.

The Eastern Orthodox countries, being the last holdout in Europe, adopted the Gregorian calendar in the 1910s and 1920s, with Greece being the last one in 1923. However, many branches of the Eastern Orthodox church still use the Julian calendar for determining holidays.

Julius Caesar established the Julian calendar. The Roman calendar had 12 months that totaled 355 days. Then in some years they would have an extra month between February and March called Mercedonius or Intercalaris to make up the lag and bring the calendar back in line with a tropical year. Sometimes, this didn’t happen because of wars or communication problems and the entire empire would be confused about the calendar date. Caesar corrected this by setting the number of days in the months and adding an intercalary day we call leap day.

So why is January the first month? There were various pre-Julian calendars and the main one in Rome at one time was a lunar-based calendar (the word month sounds like moon for a reason) with 10 months and was 304 days long. January and February didn’t even exist. That’s why September, October, November and December have root words that mean seven, eight, nine and 10. Roman King Numa Pompilius took days from each month, plus added days to the calendar, making it 355 days long, by creating January and February at the start. All days had odd numbers — which were considered lucky — except February, which had 28 days and was considered a month of purification.

When Caesar made his calendar, he kept Jan. 1 as the start. In later years after the fall of the Roman Empire, many places started years on other dates, so determining the year an event happened has always been a tricky calculation for historians. Eventually, however, most of the world conformed to the Numa, Julian and Gregorian tradition of starting on Jan. 1.

Coptic Christians to this day observe the 13-month Alexandrian calendar, which starts on the first of Thoth, or Aug. 29, unless it is a leap year, in which it starts Aug. 30. Notice it doesn’t use the Roman month names. The Coptics celebrate Christmas on what equals Jan. 7. After 2100, because of the Gregorian shift, it will equal Jan. 8.

Jewish holidays are based on the Hebrew calendar, with multiple first days of the year, depending on the purpose. Nisan is at the beginning of the calendar, and from sunset on Sept. 4, 2013, to sunset on Sept. 24, 2014, the year in the Hebrew calendar is A.M. 5774, for Anno Mundi, “in the year of the world.”

If you are curious about the origins of names of the other months, January is named for the Roman god of doors and beginnings Janus, February for a Roman time for sacrifices and purification called Februalia, March for Roman god of war Mars, April possibly for the Latin word aperire meaning “to open” as in buds, May for Roman goddess of plant growth Maia, June for goddess for protection Juno, July for Julius Caesar and August for Augustus Caesar. July and August once were called Quintilis and Sextilis, derived from Roman words for five and six.

Next week, we will explore why Anno Domini is used to enumerate our years.

 

Tribune Managing Editor Tim Engstrom’s column appears every Tuesday.