Calendar Change

by Lisa South, Certified Genealogist

I felt so smart!! They had just asked the $1,000,000 question on a popular game show and I knew the answer (believe me it was a first!). The reason I knew the answer is because it was about the calendar change and as a genealogist, I had learned the importance of understanding how this change affected historical records.

During the time of Julius Caesar, the calendar was very inaccurate and he set about to improve it. He did a great job, but there was still a small error - each year, the calendar was over 11 minutes off. It doesn't sound too important, but after 128 years it was a full day off! By the time Pope Gregory XIII decided a change had to be made, the calendar was 10 days behind the actual time. In 1582, the Pope declared that the Catholic world would begin using his new calendar, the Gregorian calendar. The Gregorian calendar is almost perfect, but to bring the world up to the right starting time, the Pope declared that the calendar would "skip" the next 10 days and that October 4, 1582 would be followed by October 15, 1582. New Years day was also changed from March 25th to January 1st.

Not everyone was ready to accept the new calendar. There were even rioters who insisted that the 10 days be given back to them. Not all countries were ready to make this change. When doing your research, find out what year the country you are researching changed over to the Gregorian calendar.

Great Britain did not accept it until 1751. By that Time, the Julian Calendar was 11 days off and so Parliament declared that September 2, 1752 would be followed by September 14, 1752. At the time, the American Colonies were part of Britain and so this is the year that the calendar change began impacting American records.

Eleven days and a change in the beginning of the New Year; is that really such a big deal? It can be! If you are searching church baptismal records and you see a record listing John, son of Henry Fear born the 5th of April 1730 and another record that lists Anne, daughter of Henry Fear the 20th of March 1730 you might conclude that these could not be siblings because they were born just a few weeks apart. With a knowledge of the calendar change the evaluation would be quite different. John was born the 5th of April, Anne was born eleven months later on the 20th of March - just before the New Year 1731 would begin (your need to remember that the year did not change in January back then).
In Quaker record, the month was usually represented with numbers. Prior to the calendar change it is important to remember that the date the 3 of the seventh month 1723 would mean the 3rd of September, not July.

Often you will see a date written Jan 12, 1757/8. This is called double dating and is a result of the calendar change. Beginning genealogists sometimes record this as "either 1757 or 1758", but actually the date is very precise. This person was born Jan 12, 1757 if using the Julian (or O.S., Old Style ) calendar but Jan 12, 1758 if you are reckoning by the Gregorian (or N..S., New Style)calendar.

You will find double dating in the months January, February and March (the ones affected by the change in the New Year). Occasionally you will find one in the other months but that is from someone doing it out of habit (the way we write the wrong year the first few months of a New Year). There were efforts to change the calendar before it actually happened, and some began double dating before the actual date of the calendar change.

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