xref: /freebsd/contrib/tzdata/calendars (revision 0b57cec536236d46e3dba9bd041533462f33dbb7)
1----- Calendrical issues -----
2
3As mentioned in Theory.html, although calendrical issues are out of
4scope for tzdb, they indicate the sort of problems that we would run
5into if we extended tzdb further into the past.  The following
6information and sources go beyond Theory.html's brief discussion.
7They sometimes disagree.
8
9
10France
11
12Gregorian calendar adopted 1582-12-20.
13French Revolutionary calendar used 1793-11-24 through 1805-12-31,
14and (in Paris only) 1871-05-06 through 1871-05-23.
15
16
17Russia
18
19From Chris Carrier (1996-12-02):
20On 1929-10-01 the Soviet Union instituted an "Eternal Calendar"
21with 30-day months plus 5 holidays, with a 5-day week.
22On 1931-12-01 it changed to a 6-day week; in 1934 it reverted to the
23Gregorian calendar while retaining the 6-day week; on 1940-06-27 it
24reverted to the 7-day week.  With the 6-day week the usual days
25off were the 6th, 12th, 18th, 24th and 30th of the month.
26(Source: Evitiar Zerubavel, _The Seven Day Circle_)
27
28
29Mark Brader reported a similar story in "The Book of Calendars", edited
30by Frank Parise (1982, Facts on File, ISBN 0-8719-6467-8), page 377.  But:
31
32From: Petteri Sulonen (via Usenet)
33Date: 14 Jan 1999 00:00:00 GMT
34...
35
36If your source is correct, how come documents between 1929 and 1940 were
37still dated using the conventional, Gregorian calendar?
38
39I can post a scan of a document dated December 1, 1934, signed by
40Yenukidze, the secretary, on behalf of Kalinin, the President of the
41Executive Committee of the Supreme Soviet, if you like.
42
43
44
45Sweden (and Finland)
46
47From: Mark Brader
48Subject: Re: Gregorian reform - a part of locale?
49<news:1996Jul6.012937.29190@sq.com>
50Date: 1996-07-06
51
52In 1700, Denmark made the transition from Julian to Gregorian.  Sweden
53decided to *start* a transition in 1700 as well, but rather than have one of
54those unsightly calendar gaps :-), they simply decreed that the next leap
55year after 1696 would be in 1744 - putting the whole country on a calendar
56different from both Julian and Gregorian for a period of 40 years.
57
58However, in 1704 something went wrong and the plan was not carried through;
59they did, after all, have a leap year that year.  And one in 1708.  In 1712
60they gave it up and went back to Julian, putting 30 days in February that
61year!...
62
63Then in 1753, Sweden made the transition to Gregorian in the usual manner,
64getting there only 13 years behind the original schedule.
65
66(A previous posting of this story was challenged, and Swedish readers
67produced the following references to support it: "Tideräkning och historia"
68by Natanael Beckman (1924) and "Tid, en bok om tideräkning och
69kalenderväsen" by Lars-Olof Lodén (1968).
70
71
72Grotefend's data
73
74From: "Michael Palmer" [with one obvious typo fixed]
75Subject: Re: Gregorian Calendar (was Re: Another FHC related question
76Newsgroups: soc.genealogy.german
77Date: Tue, 9 Feb 1999 02:32:48 -800
78...
79
80The following is a(n incomplete) listing, arranged chronologically, of
81European states, with the date they converted from the Julian to the
82Gregorian calendar:
83
8404/15 Oct 1582 - Italy (with exceptions), Spain, Portugal, Poland (Roman
85                 Catholics and Danzig only)
8609/20 Dec 1582 - France, Lorraine
87
8821 Dec 1582/
89   01 Jan 1583 - Holland, Brabant, Flanders, Hennegau
9010/21 Feb 1583 - bishopric of Liege (Lüttich)
9113/24 Feb 1583 - bishopric of Augsburg
9204/15 Oct 1583 - electorate of Trier
9305/16 Oct 1583 - Bavaria, bishoprics of Freising, Eichstedt, Regensburg,
94                 Salzburg, Brixen
9513/24 Oct 1583 - Austrian Oberelsaß and Breisgau
9620/31 Oct 1583 - bishopric of Basel
9702/13 Nov 1583 - duchy of Jülich-Berg
9802/13 Nov 1583 - electorate and city of Köln
9904/15 Nov 1583 - bishopric of Würzburg
10011/22 Nov 1583 - electorate of Mainz
10116/27 Nov 1583 - bishopric of Strassburg and the margraviate of Baden
10217/28 Nov 1583 - bishopric of Münster and duchy of Cleve
10314/25 Dec 1583 - Steiermark
104
10506/17 Jan 1584 - Austria and Bohemia
10611/22 Jan 1584 - Lucerne, Uri, Schwyz, Zug, Freiburg, Solothurn
10712/23 Jan 1584 - Silesia and the Lausitz
10822 Jan/
109   02 Feb 1584 - Hungary (legally on 21 Oct 1587)
110      Jun 1584 - Unterwalden
11101/12 Jul 1584 - duchy of Westfalen
112
11316/27 Jun 1585 - bishopric of Paderborn
114
11514/25 Dec 1590 - Transylvania
116
11722 Aug/
118   02 Sep 1612 - duchy of Prussia
119
12013/24 Dec 1614 - Pfalz-Neuburg
121
122          1617 - duchy of Kurland (reverted to the Julian calendar in
123                 1796)
124
125          1624 - bishopric of Osnabrück
126
127          1630 - bishopric of Minden
128
12915/26 Mar 1631 - bishopric of Hildesheim
130
131          1655 - Kanton Wallis
132
13305/16 Feb 1682 - city of Strassburg
134
13518 Feb/
136   01 Mar 1700 - Protestant Germany (including Swedish possessions in
137                 Germany), Denmark, Norway
13830 Jun/
139   12 Jul 1700 - Gelderland, Zutphen
14010 Nov/
141   12 Dec 1700 - Utrecht, Overijssel
142
14331 Dec 1700/
144   12 Jan 1701 - Friesland, Groningen, Zürich, Bern, Basel, Geneva,
145                 Turgau, and Schaffhausen
146
147          1724 - Glarus, Appenzell, and the city of St. Gallen
148
14901 Jan 1750    - Pisa and Florence
150
15102/14 Sep 1752 - Great Britain
152
15317 Feb/
154   01 Mar 1753 - Sweden
155
1561760-1812      - Graubünden
157
158The Russian empire (including Finland and the Baltic states) did not
159convert to the Gregorian calendar until the Soviet revolution of 1917.
160
161Source: H. Grotefend, _Taschenbuch der Zeitrechnung des deutschen
162Mittelalters und der Neuzeit_, herausgegeben von Dr. O. Grotefend
163(Hannover: Hahnsche Buchhandlung, 1941), pp. 26-28.
164
165-----
166
167This file is in the public domain, so clarified as of 2009-05-17 by
168Arthur David Olson.
169
170-----
171Local Variables:
172coding: utf-8
173End:
174