Proposal for Help Date Fields

Profile manager: Joe Cochoit [send private message]

Calendar Adjustments

The introduction of the Gregorian calendar in 1582 to replace the Julian calendar still causes problems and confusion to this day. Its slow adoption around the world meant that any given day had a different date depending on where you lived. During this same period there was a shift in what was considered to be the first day of the year from March 25 (Old Style) to January 1 (New Style). In examining records between 1582 and 1752, care must be taken in determining which calendar and which new year start date was being used.

• Rule 1: We use the day and month found on the document. This may seem like obvious common sense. Shifting from one calendar to another can also cause a shift in the days–don't do it.
• Rule 2: We assume the year started on January 1^st. This does mean we often have to change the year found in a document.
• Rule 3: For dates requiring double dating, the new style (larger) year should be in the data field, while the double date should appear in the narrative biography.
  
  For example, Isaac Newton died on 20 March 1726 Old Style which is 20 March 1727 New Style. The year 1727 goes in the data field while the narrative biography should include the date 20 March 1726/7. Note that this is not a change from the Julian calendar to the Gregorian calendar because we did not change the date.

For more detail on calendars and dates please see the Dates, Calendars and Genealogy page.