#52Ancestors, Week 40, Ten

Ten what ? Toes and fingers…Years…Children…Siblings…Living at #10…10xggrandparents…

Well what about the Gregorian calendar ? It is the one which most of us use every day. I don’t know lots about it, except that when we look back in time there are some dates which are dual dated.

And keeping to the TEN theme, it happened in October 1582.

Up until then the Julian calendar had been in use, since 46BC – time for a change in more ways than one then. The Julian calendar was similar in many ways to the Gregorian calendar; it had 12 months and included a leap year every four years. It was first introduced after Julius Caesar consulted with an astronomer named Sosigenes. It was based on a tropical year – calculated by the Earth’s revolutions around the sun. Leap days were to be added to February which was the last month of the year. by 450BC February had moved to its current position as 2^nd month of the year.

Leap years were not observed initially due to a counting error and then occurred every three years before being altered to be every four years. However, every four years was still too often and by the 16^th century important religious holidays were out of sync with astronomical dates such as equinoxes and solstices. The calculations adopted by Caesar were 11 minutes short over each solar/tropical year.

Pope Gregory XIII was concerned at the non-alignment of astronomical and religious events and issued a papal bull to adopt the new calendar. This calendar changed the frequency of leap years; to only occur in years which were divisible by 4 or 400 and not in years which are divisible 4 and 100 (making 1900 an exception). The calendar, although named for Pope Gregory, is actually an adaption of a calendar designed by Luigi Lilio (Aloysius Lilius) – 1510-1576 – an Italian scientist.

Of course it didn’t just happen overnight, although in some respects it did.

Catholic countries adopted it first as was decreed by the Church. But Protestants feared that the calendar was an attempt by the Catholic Church to silence them. The decree stated that the calendar the day after the Julian calendar October 4, 1582 would be Gregorian calendar 15 October 1582.

Most of the Protestant European countries also adopted the calendar by 1700. Britain held off. By the time they changed in September 1752 the difference between the Julian calendar and the Gregorian was ELEVEN days. Imagine the confusion travelling back and forth between France and Britain ! Jetlag and the International dateline has nothing on that.

In Britain in addition to skipping eleven days in September, the start of the year was moved from Lady Day (March 25) to January 1, 1752. For most users of the Julian calendar January 1 had been the start of the year since its inception in 46BC. During the Middle Ages European countries replaced it with dates which held more religious significance; December 25 and March 25 (the Feast of Annunciation).

The longer countries waited to adopt the calendar the more days they needed to miss. When Russia (1918), Greece (1923) and Turkey (1926) joined they needed to skip THIRTEEN days.

What happened to all those birthday celebrations that would normally have fallen in those “skipped” TEN, eleven, twelve or thirteen days ? Imagine telling your kids they don’t get a birthday this year, at least that only happens for leap babies now.

The calendar still isn’t perfect – by 4909 it is estimated that the Gregorian calendar will be one day ahead of the Julian. At least we wont need to worry about that correction.