Double Dating

double dating genealogyIf you’ve been doing any genealogy research from the 1500s until the mid 1700s, particularly in any English or early American regions, you may have noticed a little anomaly with the way dates were recorded. Specifically, dates with 2 years. A date such as “January 6th, 1692/3” would be such an example. In genealogy, this is known as double dating.

I found several instances of this personally, and always attributed it to some sort of clerical error or even that the year was being estimated. But after a while, I started to wonder and did a little further research. There was quite an interesting story behind this after all.


Before 1582, the Julian calendar was still in use and used March 25th as the first day of each new year. But then it was discovered that this old form of calendar was not accurate, and that the seasons were getting out of synch with the calendar dates. So Pope Gregory XIII had a new calendar created, and we now know that as the Gregorian calendar (and we are still using it today).

But this new calendar now marks January 1st as the start of the year, and this is where double dating comes into play.

For decades, there was a mix of usage between the old and new calendars, and it wasn’t until 1752 that the British government officially and formally adopted the Gregorian system of dating. During the time when both systems were in use, it became a problem to record dates between January 1st and March 25th.

Anyone using the “new” system would be into the next year after January 1st, but anyone still on the old system would consider it to be the same year until March 25th. So any dates in this time window could have 2 years, and that is exactly how they were written.

If your genealogy software doesn’t allow you to enter double dates (and there is a good chance it might not), you would be the most accurate to use the second date considering it reflects the date using the Gregorian calendar. I’d suggest making a little note about the double date, just as a historical reminder of how it was originally recorded.