By Daniel Hubbard | March 22, 2010
I assume that everyone doing British or British Colonial research is getting ready for New Year’s Eve. It’s time to uncork another of those pre1752 bottles you have hidden away, put on your homemade tri-cornered party hat and get together with fellow genealogists.
Ok, maybe not, but the fact that New Year’s Day is coming up, in a sense, is true and that is a reason why I started to give a talk about understanding calendars and why I’ve been waiting for this time of year to roll around ever since I started this blog. As calendric cognoscenti know, by the “old style” calendar used in Britain and the colonies until 1752, March 25 was the first day of the year.
I am cheating in a bit, though. The calendar in use was also a Julian calendar that had fallen out of alignment with the seasons, and not the Gregorian calendar now in use. As we will see, the two calendars do not line up. Also, March 25 was the start of the civil year but almanacs started on January 1, using what was sometimes called the “historical year.” During the gap from January 1 to March 24 when the year had a different number depending on whether it was civil or historical, people often used double dating, that is, they specified both years at the same time in the same date. This is the meaning of dates like February 12, 1671/2. It was 1671 in the civil year but already 1672 in the historical year.
The Julian calendar itself, independent of the day that began the year, had a problem as well. It was meant to be a solar calendar, which means that roughly speaking, on average one calendar year should be the amount of time taken by the Earth to go once around the sun. It turned out that it wasn’t quite reproducing the solar year. This became important because Easter is calculated using the spring equinox and the Church had defined the equinox to occur on March 21 instead of relying on observation. So, any inaccuracy in the calendar meant that Easter would drift away from the true equinox. By the time the more accurate Gregorian calendar was adopted by Catholic countries in the 1580s, the Julian calendar was off from the sun by 10 days. By the time the British Parliament approved the adoption of the Gregorian calendar in Britain and the colonies, eleven days needed to be dropped from the calendar to realign it with the sun. By now, the Julian calendar then in use would be off by thirteen days and that means that the old March 25 doesn’t occur until our April 7. It isn’t even easy to decide when to put on that party hat.
Many genealogists love old maps and I am certainly one of them. Maps show you where people lived, where the canal or railroad ran, the location of the trail through the wilderness or the pass over the mountains. As helpful as that might be, it only helps you locate your ancestors in space. Family historians should love old calendars as well. Calendars are our maps of time. Understanding the calendars that our ancestors lived under is like understanding the Cumberland Gap, the Erie Canal or the Oregon Trail. Each explains how people got from point A to point B but only calendars explain how they got there though time.
We are so used to the calendar simply working that we take it for granted. We celebrate the new year and we are somewhat interested when an extra day is added to February. Occasionally, we might also wonder why February has so few days but that is normally the limit of our interest.
Yet historically, calendars are not so clear cut. Different places have had different calendars. The length of the year, the timing of any leap days and their placement in the year, the date that marks the new year and the moment from which the years are counted can all be different from one calendar to another. The number and lengths of the months and weeks can be different. The calendar in use one year might not be the same as was used the year before. The calendar used “here” might not be the same as the calendar used “there” even if “there” was only a few miles away. As we’ve seen, there might even be different definitions of the year in the same place, used by the same people. Interpreting a date means knowing the calendar in which it was expressed and if the document is not original, what “correction” might have been placed on that date.
How much could the calendar change? In England, Wales, Ireland and the colonies the year 1751 was officially only 282 days long because it ran from March 25 only to December 31 because the start of the new year was moved. Notice that “Britain” did not make this first change. Scotland had been using a calendar that began the year on January 1 for 152 years. The following year September 2 was followed the next day by September 14 as the calendar was put back in line with the seasons and changed from Julian to Gregorian.
Calendar changes, some major, some minor, occurred in different places at different times. The calendar used for an ancestor’s documents can depend on calendar reform, shifting borders, religion and that ancestor’s own movements with all these factors interacting. Knowing what calendar was being used and how dates were being written is not always easy but it can make the difference between a hypothesis having impossible timing and it being an obvious explanation. Perhaps the most important thing to understand about calendars is that the moment you see an old date, you need to ask yourself, “Do I understand this?”
Footnote: Julian vs Gregorian
The basic difference between these two calendars is how leap days are used to attempt to keep the calendar year aligned with the seasons. The Julian calendar has a leap day every four years without exception. That makes the average year slightly too long. The Gregorian calendar eliminates three leap days every four hundred years to keep in better relation with the solar year. Years that end in “00” would be leap years by the Julian calendar but are not leap years in the Gregorian calendar unless they can be evenly divided by 400. So, in the Gregorian calendar 1800 and 1900 were not leap years and 2100 will not be a leap year but 2000, being divisible by 400, was a leap year.Twitter It!