Double Dating

If you have ancestry from the UK or even the early American colonies, during the period between the late 1500s and mid 1700s, you may have noticed a lot of people with 2 years for their vital statistics. Records such as "born February 5th, 1720/21". Given that these records are hundreds of years old, I always just assumed that the years hadn't been recorded properly or that the actual year was an estimate.

I finally came across too many instances of this, and decided that it must mean something more than a clerical error. And it was. This is a common practice for that time period, and it's referred to as "double dating". And here is what it means.

Prior to 1582, most of the world was using the Julian calendar and considered March 25th to be the first day of the new year. But in 1582, Pope Gregory XIII realized that the Julian calendar was incorrect just enough that the seasons were slowly shifting on the calendar. He devised a new calendar (appropriately named the Gregorian calendar) to adjust for the slight problems of the Julian one. This is the calendar we are still using today.

But the Gregorian calendar had January 1st as the first day of the year. And herein lies the problem.

Not everyone adopted the new calendar at the same time. For decades, Britain and the new American colonies stayed with the Julian calendar. They didn't start to use the Gregorian dating until 1752. I should say the government didn't officially adopt the new calendar until then. Most of the populous had by that point.

So anything that occurred between January 1st and March 25th could have been recorded as one year or the next, depending on what system you were using. It became custom to write down the both years. As I mentioned above, February 5th was still part of 1720 by one system, but in 1721 by the new system. So the date was kept as Feb 5th, 1720/21.

Older or more simple genealogy programs aren't capable of handling dates in this style. I suppose it would be more accurate to choose the second year if you had to do so, but you should make a notation that the record was actually made up of a "double date". It's a part of history that shouldn't be erased.