From a presentation by Stephanie Yates at the February 28, 2004 Gastineau Genealogical Society Meeting
Solar
Egyptian
Julian
Gregorian
French Republican, 1793-1806
Sweden's Adjustments
British North America Adjustments
Points to Remember in the Genealogy World
A Comment Received by a Correspondent Regarding the British North America Adjustments
Solar Calendar
Based on astronomical cycles
Day: Rotation of earth on its axis
Month: Revolution of the moon around earth
Year: Revolution of the earth around the sun
Egyptian Calendar
365.25636 days in a year
Most accurate calendar ever used
Julian Calendar
Created by an Egyptian for Julius Caesar
365 days per year divided into 12 months
Adjustment for the additional 1/4 day per year created a "leap year" every four years, adding an extra day to Feb
The calendar averaged 365.25 days per year, but it was 0.00636 days off from the Egyptian
The time difference leaves the Julian calendar one full day behind every 128 years
Implemented in 45 BC by adding 90 days to the established Roman calendar
Instead of weeks, each month was divided by 3 particular points:
Kalends: first day of the month
Ides: 13th of each month, except it was the 15th in March, May, July and October
Nones: Eight days before Ides
Gregorian Calendar
Between 45 BC and 1582 AD, the Julian calendar was 10 days behind the astronomical cycles Oct 1582, Pope Gregory XIII subtracted 10 days from the calendar to make up the difference
Also made a century year a leap year, but only if it could be divided evenly by 400, causing 3 less leap years every 400 hundred years
This calendar is one day behind every 3,225 years
Changed the first day of the year from March 25 to Jan 1
Most of the Catholic countries changed to the Gregorian calendar in 1582 and the Pope ordered that the day following Oct 4, 1582 would be Oct 15, 1582.
Protestant countries did not follow the change made by the Catholic church
See attached list for country adoption dates
Alaska: Oct 1867 when purchased from Russia
French Republican Calendar, 1793-1806
France adopted the Gregorian calendar in Dec 1582
Napoleon introduced the French calendar on Nov 24, 1793, turning 1792 to Year 1 based on the French Revolution
Abolished Jan 1, 1806 in exchange for the Catholic Church recognizing Napoleon as the Emperor of France
Sweden's Adjustments
Skipped every leap year from 1700 to 1740 to gradually change to the Gregorian calendar by Mar 1, 1740
By accident, 1704 and 1708 were counted as leap years, so Sweden converted back to the Julian Calendar by adding an extra day in 1712
In 1753, Sweden dropped 11 days from the calendar to change to the Gregorian calendar
British North America Adjustments
By 1752, the Julian calendar was 11 days off
11 days were removed after Sep 2, 1752, so the day after Sep 2 was Sep 14, 1752
Following the Gregorian calendar, the first day of the year was changed to Jan 1, so 1752 was only 280 days long in the British lands
Included England, Scotland, Wales, Ireland, and Britain's North American colonies.
A Comment Received by a Correspondent Regarding the British North America Adjustments:
"Hi,
At this web page: http://www.ggsalaska.org/calendars.htm the following statement was made:
"Following the Gregorian calendar, the first day of the year was changed to Jan 1, so 1752 was
only 280 days long in the British lands"
Not completely accurate, but I see what you're trying to get at.
1751 in England was 282 days long i.e. 25 March to 31 December 1751, but in Scotland it was
365 day long i.e. 1 of January to 31 December 1751.
Incidentally, 1752 was 355 days long in "British lands" e.g. 366 -11 (1752 was a leap year)."
From a correspondent in Australia
Points to Remember in the Genealogy World
After the British converted to the Gregorian calendar in 1752, "double dating" occurred
"Double dating" indicates a date before 1752 that is between Jan 1 and Mar 24; supposedly as a genealogist, double dating should be used and is not typically found written on old records of that time (before 1752)
Example: George Washington was born Feb 22, 1731 (Julian calendar was in effect), but we celebrate his birthday as Feb 22, 1732 based on the Gregorian calendar, so his birthday should be written as Feb 22, 1731/1732
**Therefore, any date found on British records originating Jan 1 through March 24 before 1752 is one year off (add one year to the year listed)
Dates recorded in Sep 1752 can be 11 days off, but only in the situation where the death day is expressed by the number of days
Ex: Gravestone shows a person died "at the age of 78 years, 4 months, and 9 days" and the death date was 21 Sep 1752; the birthday is actually Sep 1, not Sep 12
Other ethnic groups that settled in the British colonies before 1752 may have been using the Gregorian calendar, such as Dutch settlers in NY and NJ, since their homelands converted to the Gregorian calendar before the settlers came to the British colonies
The Quakers, before Sep 1752, wrote months based on its position in the Julian calendar year
Ex: 1746, 3rd mo, 28th day is May 28, 1746
Reference: Heritage Quest, "It's About
Time: Calendars and Genealogical Dates,"
Genealogy Bulletin, Vol 15, Number 2, Issue
50, March/April 1999, pgs 1-13.