Use this form to convert dates between the Julian and Gregorian Calendars.
- To convert a Julian Calendar date to the Gregorian Calendar, key a "day month year" date in the Julian Date textbox.
- To convert a Gregorian Calendar date to the Julian Calendar, key a "day month year" date in the Gregorian Date textbox.
Details
- Key dates in the format "day month year" where day and year are numbers and month is a month name or abbreviation.
Example: 11 Feb 1731
- Day numbers must be one or two digits. This form does not verify that you have entered a valid day number for the given month and year.
- Month names must be three-character abbreviations (Jan, Feb, Mar, Apr, May, Jun, Jul, Aug, Sep, Oct, Nov, Dec) or the full names (January, February, March, April, May, June, July, August, September, October, November, December). Do not use month numbers.
- Year numbers must be three or four digits.
- The dates must be in the common era, i.e., 1 Jan 0001 to present.
- Set the "Julian New Year's Day" value to the day the year number incremented in the era and locale of interest. Key a day number and a month name or abbreviation.
The day when the year number increased varied according to the era and locale. In England in 1556, the new year began on March 25, although civil, liturgical, and tax calendars in England may not have all used the same New Year's Day. Meanwhile, in Spain in 1556, the new year began on January 1.
Country Details
The table below indicates when several European countries adopted the Gregorian calendar. It is incomplete. For a more complete list, see Wikipedia.
| Country / Region | Adoption Year | Last Julian Day | First Gregorian Day |
|---|---|---|---|
| Austria (Catholic states) | 1583 | 5 OCT 1583 | 16 OCT 1583 |
| Bulgaria | 1916 | 31 MAR 1916 | 14 APR 1916 |
| Denmark | 1700 | 18 FEB 1700 | 1 MAR 1700 |
| France (most areas) | 1582 | 9 DEC 1582 | 20 DEC 1582 |
| Germany (Catholic states) | 1583–1584 | ||
| Great Britain & Colonies | 1752 | 2 SEP 1752 | 14 SEP 1752 |
| Greece | 1923 | 15 FEB 1923 | 1 MAR 1923 |
| Hungary | 1587 | 21 OCT 1587 | 1 NOV 1587 |
| Italy | 1582 | 4 OCT 1582 | 15 OCT 1582 |
| Norway | 1700 | 18 FEB 1700 | 1 MAR 1700 |
| Poland | 1582 | 4 OCT 1582 | 15 OCT 1582 |
| Portugal | 1582 | 4 OCT 1582 | 15 OCT 1582 |
| Switzerland (Catholic Cantons) | 1583-1584 | ||
| Switzerland (Protestant Cantons) | 1700–1701 | ||
| Switzerland (Unified) | 1812 | ||
| Prussia | 1610 | 22 AUG 1610 | 2 SEP 1610 |
| Romania | 1919 | 31 MAR 1919 | 14 APR 1919 |
| Russia | 1918 | 31 JAN 1918 | 14 FEB 1918 |
| Spain | 1582 | 4 OCT 1582 | 15 OCT 1582 |
| Strasbourg | 1682 | 5 FEB 1682 | 16 FEB 1682 |
| Sweden (including Finland) | 1753 | 17 FEB 1753 | 1 MAR 1753 |
| Yugoslavia | 1919 | 31 MAR 1919 | 14 APR 1919 |
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John Cardinal