Julian to Gregorian Calendar

When the original change occurred there really were people who believed the Church had "stolen" 10 days from their lives… and they would now die 10 days earlier than originally intended. Also, Protestant and Eastern Orthodox controlled lands ignored the Roman Catholic decree.

Does this mean that official documents dated after the changeover refer to the Gregorian
? Not a chance. Some people added "OS" (Old Style) or "NS" (New Style) while others just wrote the day… using whichever calendar date that made sense to that person. Be very careful when using dates around a changeover year, and for some years after. It really is hard to get people to change old habits…

The Julian Calendar is currently 13 days behind the Gregorian Calendar (2003). Many Orthodox Churches still use the Julian Calendar as the standard for the church.

Country/Region Year Days Comments
Italy, Portugal, Spain 1582 10 4 Oct 1582 Julian was followed by 15 Oct 1582Includes all Spanish colonies and possessions, such as Mexico
France 1582 10

20 Dec followed 9 Dec. French possessions, such as Louisiana in North America, used the Gregorian Calendar from their founding.

Luxembourg 1582 10 25 Dec followed 14 Dec
Zeeland, Brabant, and the Staten Generaal in modern-day Netherlands 1582 10 25 Dec followed 14 Dec
Limburg and several other provinces 1582/3 10 31 Dec followed 20 Dec. 1 Jan 1 followed 21 Dec in some cases Wonder what people thought of not having Christmas?
Holland 1853 10 12 Jan followed 1 Jan
Switzerland 1583-1812 Parts of Switzerland made the change over many centuries, starting in 1583 and only being complete in 1812.
German Roman Catholic states, Belgium, and part of The Netherlands 1584 10  
Hungary 1587 10  
Prussia 1610 10  
Alcase 1682 10  
Protestant German states including Prussia 1700 11 Many of these states calculated Easter using the Tycho Brahe's method, but used the new calendar for civil and commercial affairs. They adopted the Gregorian rules for calculating Easter in 1776.
The Netherlands 1700 11 All of The Netherlands used the same calendar in this year.
Denmark, Norway 1700 11  
Sweden starts change 1700   Sweden phased in the change from 1700 to 1740 by exluding leap days.
Sweden reverts back to Julian Calendar 1712    
Tuscany 1750 11  
England, Scotland, Ireland, and Wales 1752 11 Wednesday, September 2, 1752 gave way to Thursday, September 14th. The first day of the year was also changed from March 25 to January 1.
English colonies including present-day USA, Australia, and Canada 1752 11  
Finland 1753 11  
Sweden 1753 11 Sweden finally made the switch in one change when 17 Feb was followed by 1Mar
Lorraine 1760 11 28 Feb followed 16 Feb
Alaskan Territory 1867 11 This change to the new calendar occurred when the United States purchased Alaska from Russia.
Japan 1873 11  
Egypt 1875 11  
Thailand 1889 Kinda…
China 1911   Again in 1949… not sure when they reverted.
Albania 1912    
Latvia 1915?    
Lithuania 1915    
Bulgaria 1916    
Russia 1918 12

14 Feb followed 31 Jan 

The Revolution of 1918 allowed reformers to adopt the calendar in use by most of their trading partners. The Russian Imperial Navy and academics dealing with westerners had been using the new calendar for many years (decades in some cases) but the internal civil calendar did not change until 1918.

Estonia 1918 12  
Romania 1919    
Yugoslavia 1919    
Greece 1923 or 1924 12 There is some disagreement about when Greece changed.
Iran 1925 12  
Turkey 1927 12