HISTORY BY NUMBERS
Andrew Chapman tries to get his head around the nuances of the Julian and Gregorian calendars
Andrew Chapman looks at the nuances of the Julian and Gregorian calendars.
The current issue of the SoG’s Genealogists’ Magazine (Vol 32 No 6) contains a fascinating article by Peter Maggs entitled ‘Confusion and myth in the Gregorian calendar reform’. I urge you to read it, although I will mention a few of its salient points here, as well as looking at the implications of calendar reform in general for family historians.
The traditional Julian calendar, named after its proponent Julius Caesar, was adopted by the Romans, and therefore across Europe, in 45BC. It’s not as unfamiliar as one might imagine – in fact, the 12 months’ lengths were exactly the same as we use today. The main innovation of Julian reform was to add a leap day to February every four years.
However, this was not enough to stop a gradual drift between the humanimposed calendar and the wilful ways of nature: the Julian calendar ends up being slightly too long for the solar year, to the tune of one day every 128 years. As the centuries, roll by, these things start to matter, with the calendar adrift from important events such as the equinoxes and solstices.
The Gregorian calendar (named after Pope Gregory XIII) proposed a fairly simple adjustment to this, namely that years evenly divisible by 100 are not leap years – unless they are evenly divisible by 400. So 1900 was not a leap year – but the millennial year of 2000 (OK, let’s not get into the debate about the millennium actually being in 2001) was. This adjustment makes the average year length 365.2425 days, which is enough to mean the calendar only gains one day against the sun every 3030 years.
Calendar reform came late to Britain (and its colonies, including America) – Gregory introduced his reforms in 1582 (one can only imagine the bureaucracy involved) and they spread across much of Europe, such as France, Spain and Italy, straight away. But this was the reign of Elizabeth I in England, and Catholic ideas were not welcome. Britain only joined Europe, as it were, as a consequence of the Calendar (New Style) Act of 1750; the result was that 2 September 1752 segued into 14 September to play catch-up.
As Peter Maggs points out, the stories of riots over the ‘lost’ 11 days are apocryphal, sparked off by a satirical barb in a Hogarth painting. But there were certainly complications to deal with. For example, people turning 21 had to wait an extra 11 days before celebrating their majority. More complicatedly, in 1752 New Year’s Day moved from the traditional 25 March to 1 January, so we end up with the following: • 31 December 1750 was followed by 1
January 1750 (as was traditional) • 24 March 1750 was followed by 25 March
1751 (ditto) • 31 December 1751 was followed by 1 January 1752 (New Year reform) Our modern tax year from 6 April is a lingering vestige of the old start to the year. Oh, and Scotland had already moved New Year to 1 January back in 1600.
For family historians, all of this can make researching the 18th century rather confusing. For example, Old Style dates can create situations such as a baby being born in October 1740 and dying in January 1740, because dates from 1 January to 24 March inclusive were part of the ‘year before’, as it were. This also implications for assuming an ancestor was illegitimate, when in fact they were not. The recommendation is to use ‘double dating’, ie write dates from 1 January until 24 March from 1582 to 1752 in both Old and New Style (OS/NS) form: eg 20 March 1649/50. You can find a useful calendar converters online at www. fourmilab.ch/documents/calendar/ and www. stevemorse.org/jcal/julian.html.
You may also want to check whether your genealogy software can cope with double dating: some GEDCOM interpreters may parse a double date by reading in the first (Old Style) one. GEDCOM 5.5 has a provision for specifying whether a date is Julian or Gregorian, and indeed for ‘date phrases’ where the dual information can be stored, but different packages may interpret that in different ways (for advice on Family Historian, for example, see http:// bit. ly/2tTwqmi).
Incidentally, if you have Quaker ancestors, they typically indicated months by a number, with March the first month before the 1752 reforms and January thereafter.
If we’re inclined to smirk at these historical quirks, did you know that Daylight Saving Time never ended in 1968? Britain remained an hour ahead of GMT until 31 October 1971. I was born on the first day of a month in this era, at half-past midnight: so does this mean my birthday is actually in the previous month?!
Meanwhile, if you’d like a taste of life before the Gregorian reforms, take a trip to the remote Scottish island of Foula, where the 30- odd inhabitants still keep a little of the Julian calendar, allowing for the current 12- day difference from the Gregorian. They celebrate Christmas on 6 January – and New Year on 13 January.
‘Give us our eleven days’ – a detail from William Hogarth’s An Election Entertainment