Double Dates

No, we're not talking about a pair of couples out to dinner - this is all about the worldwide transition from the Julian (Old Style) Calendar to the Gregorian (New Style). This can cause some confusion to the new researcher.

In the Julian Calendar, the year ended on March 25th. The complicated reasons for calendar reform I shall leave to others better qualified, as my concern is to provide the facts as they apply to the family historian.

The Gregorian Calendar was first introduced by Pope Gregory XIII, and it addressed the problem of an imprecise Julian dating system that caused gradual shifts in the calendar - in a nutshell, the vernal (Spring) equinox had shifted from 21st March in the year 325 to around the 11th March by 1582, shifting Easter along with it. Along with more complex leap year rules to ensure that a calendar year, on average, ran parallel to the lunar year, the change from Julian to Gregorian calendar also included the removal of 10 days from the calendar to re-align the dates to the original spring equinox.

Many Catholic European countries adopted the Gregorian Calendar throughout the latter part of 1582, but protestants resisted change and it occurred very gradually throughout protestant countries and their colonies.

The British government adopted the Gregorian calendar at home and in her colonies (including America) in 1752, by which point the time shift had increased to 11 days, so Wednesday 2nd September 1752 (Julian) was followed by Thursday 14th September.

From the first introduction of the Gregorian calendar in 1582 until its adoption in Britain, it was very common for scribes to record a date falling between 1st January and 25th March with both years, so you will often see dates recorded as 1st January 1730/1 or similar. This is what we refer to as double-dating.

The British tax system never changed to adjust for the adoption of the Gregorian calendar, which is why your tax year still starts in early April.

One of the key issues for the family researcher is the fact that an event recorded in February 1730 actually occurred before one in December of the same year. I can't count the number of times, during my learning curve, that I discounted a child of a family because a legitimate birth appeared to happen some months before the wedding or I missed a child's death because it seemed to occur before the birth.

You will also find that some family tree software will ring automated alarm bells if you say a child was born in December 1730 and died in February 1730, telling you this can't possibly be right.

This brings about the next problem - do you record the events as they were recorded at the time, or do you translate them to the new style calendar to ensure your family tree software can apply its own logic? I haven't found a definitive answer for this, but I would always recommend making a decision to do one or the other from the outset and stick to that decision. It is also useful to ensure that you make it clear in the notes which calendar you have used, including the double-date. You don't want to find yourself with a tree containing a few thousand people where you've used a mixture of Julian and Gregorian dates and trying to correct them later.

Owing to the limitations of family tree programmes, my advice would be to record all dates in the Gregorian calendar and comment on each record where this has occurred. I hope one day that software will be developed with this problem accounted for, and the programme will be able to cope with double-dates.