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Date Complexity

Amanda Ross edited this page Feb 11, 2020 · 80 revisions

Table of Contents


Adoption of Gregorian Calendar

Date Complexity: Adoption of Gregorian Calendar Compared to FRUS Publication

Adoption of Gregorian Calendar, by Jurisdiction

Jurisdiction Date of Adoption
Albania 1912
Bulgaria 1916
China 1912
Denmark Pre-FRUS
Egypt 1875
Estonia 1918
Finland Pre-FRUS
France Pre-FRUS
Great Britain Pre-FRUS
Greece 1923
Italy Pre-FRUS
Japan 1873
Korea 1896
Latvia 1915
Lithuania 1915
Luxembourg Pre-FRUS
Norway Pre-FRUS
Poland Pre-FRUS
Portugal Pre-FRUS
Romania 1919
Spain Pre-FRUS
Sweden Pre-FRUS
Swiss Cantons Pre-FRUS
Turkey 1926
United States Pre-FRUS
USSR 1918
Yugoslavia 1919

Calendar Examples and Conversion Resources

calendar="brazilian-republic"

Official documents such as treaties may include a parallel date phrase referring to the year in relation to the establishment of the republic of Brazil.

<date when="1889-12-23" calendar="gregorian brazilian-republic">
  the 23d of December, 1889, first year of the Republic
</date>
<date when="1906-06-30" calendar="gregorian brazilian-republic">
   June 30, 1906, 18th of the Republic
</date>

calendar="chinese-era"

Prior to 1912, Chinese dating systems often referred to the reign or era of particular rulers of China.

<date when="1904-03-09" calendar="chinese-era chinese-lunisolar gregorian">
  Kuanghsü XXX year, first moon, 23d day. (March 9, 1904.)
</date>
<date when="1901-01-14" calendar="chinese-era gregorian">
  <hi rend="smallcaps">Kuang Hsü</hi>, <hi rend="italic">26th year, 
  11th month, 24th day</hi> (<hi rend="italic">January 14, 1901</hi>)
</date>
<date when="1926-01-16" calendar="chinese-era">
  Of the Chinese Republic the fifteenth year, the first month, 
  and the sixteenth day
</date>
Reign Years Reign Title Other Names and Variant Spellings
1736–1795 Emperor Qianlong Qiánlóng, Gāozōng, Hónglì
1796–1820 Emperor Jiaqing Rénzōng, Jiāqìng, Yóngyǎn
1821–1850 Emperor Daoguang Dàoguāng, Xuānzōng, Mínníng
1851–1861 Emperor Xianfeng Wénzōng, Wenzong, Yìzhǔ
1862–1874 Emperor Dongzhi Mùzōng, Muzong, Zǎichún, Tongzhi, Tungchi, Tung-Chi, Tung-Chih, T’ung Chi, [Fungchi (?)], [Dochi (?)]
1875–1908 Emperor Guangxu Kuanghsü, Kuang Hsü, Kuang Sü, Dézōng, Tezong, Zǎitián
1909–1911 Emperor Xuantong Gongzōng, Pui

Sources:

calendar="chinese-lunisolar"

The traditional Chinese calendar is a lunisolar calendar. While it has been supplanted by the Gregorian calendar for civil purposes, the Chinese calendar is still used in the determination of community events such as festivals.

<date when="1901-10-10" calendar="chinese-lunisolar gregorian">
  Eighth moon, 28th day (October 10, 1901)
</date>
<date when="1904-03-09" calendar="chinese-era chinese-lunisolar Gregorian">
  Kuanghsü XXX year, first moon, 23d day. (March 9, 1904.)
</date>

calendar="chinese-republic"

Official documents such as treaties may include a parallel date phrase referring to the year in relation to the establishment of the republic of China.

<date when="1912-03-10" calendar="gregorian chinese-republic">
  March 10, 1st year of the Republic of China [1912]
</date>
<date when="1916-03-27" calendar="gregorian chinese-republic">
  March 27, 1916 (27th day of the third month of the fifth year of the Chinese Republic)
</date>

calendar="ethiopian-geez"

The Ethiopian Ge’ez calendar is used in Ethiopia's civil society as well as the Orthodox Church in Ethiopia and Eritrea. The solar-based Ethiopian calendar is related to the Coptic and Julian calendars. According to TimeAndDate.com, "The main point of difference lies in the calculation of the date of the birth of Jesus, which means that the Ethiopian calendar is 7 to 8 years behind the Gregorian calendar."

<date when="1914-12-24" calendar="ethiopian-geez gregorian">Written
  15th Tehsass 1907 (Abyssinian date) Year of Grace Adis Ababa.<lb/> 
  24th of December 1914 (European date)</date>
<date when="1927-04-30" calendar="ethiopian-geez gregorian">
  <hi rend="italic">22nd of Mazia, 1919</hi> 
  (<hi rend="italic">April 30, 1927</hi>)</date>
Month in Ethopian Ge’ez Calendar Other Names and Variant Spellings Amharic
Mäskäräm Maskaram, Maskarram መስከረም
Ṭəqəmt Ṭəqəmti, Teqemt, Teqemti, Tekemr ጥቅምት
Ḫədar Hedar, Hadar ኅዳር
Taḫśaś Tahsas, Tehsass ታኅሣሥ
Ṭərr Ṭərri, Tubah, Tarr ጥር
Yäkatit Yakatit, Läkatit, Lakatit, Yekatit የካቲት
Mägabit Magabit, Makawit መጋቢት
Miyazya Mazia, Miaziah ሚያዝያ
Gənbo Gənbot, Genbo, Genbot ግንቦት
Säne Sane, Sanni ሰኔ
Ḥamle Hamle ሐምሌ
Nähase Nahase, Nashi ነሐሴ
Ṗagʷəmen Ṗagume, Pagwemen, Pagume, Quaggimi ጳጐሜን, ጳጉሜ

calendar="gregorian"

The Gregorian calendar is widely used worldwide and is the calendar system used in the international standard for dates and times (ISO 8601). The solar-based Gregorian calendar is also known as the Western calendar or Christian calendar.

Because the U.S. Department of State is headquartered in the United States, the majority of datelines in FRUS refer to the Gregorian calendar or have parallel date statements.

<date when="1904-04-27" calendar="gregorian">
  the 27th of April, 1904
</date>
<date when="1982-09-21T13:45:00" calendar="gregorian">
  September 21, 1982, 1345Z
</date>
<date when="1917-03-18" calendar="julian gregorian">
  <hi rend="italic">March 5/18, 1917</hi>
</date>
<date when="1918-03-01" calendar="gregorian julian">
  March 1/February 16, 1918
</date>
<date when="1927-04-30" calendar="ethiopian-geez gregorian">
  <hi rend="italic">22nd of Mazia, 1919</hi> 
  (<hi rend="italic">April 30, 1927</hi>)</date>

calendar="haitian-republic"

Official documents such as treaties may include a parallel date phrase referencing the year of the republic of Haiti (formerly Hayti).

<date when="1906-08-28" calendar="haitian-era">
  August 28, year 103 of the independence
</date>
<date when="1890-05-28" calendar="gregorian haitian-republic">
  the 28th of May, 1890, the eighty-seventh year of independence
</date>

calendar="hijri"

The Islamic calendar, or Hijri or Muslim calendar, is a lunar calendar, whose time reckoning is tied to the phases of the Earth's moon. The Hijri calendar is used by many Muslim-majority countries and by Muslims around the world to determine the dates of religious events and observances.

<date when="1901-08-18" calendar="hijri">
  Year 1319, Jamad-el-Ewel the third
</date>
<date when="1942-05-13" calendar="hijri gregorian">
  27 Babee El Thani 1361 (13 May 1942)
</date>
Month in Islamic Calendar Variant Spellings Arabic
Muḥarram Muharram, Moharram مُحَرَّم
Ṣafar Safar, Saffar, Sefer صفر
Rabī‘ al-awwal Rabi' al-awwal, Rebbi-al-ewel, Rabih ربيع الأوّل
Rabī‘ ath-thānī Rabī‘ al-Thānī, Rabī‘ al-Tānī, Rabī’ al-Ākhir, Rabi el tami, Rabee El Thani, Rabi’Tani, Rebbi-ul-Akbir, Rebi-ul-Ewel, Rabih بيع الثاني , ربيع الآخر
Jumādá al-ūlá Ǧumādā al-ʾAwwal, Jumada al-awwal, Jumada al-ula, Jumada al-Ula, Jumada, Jumada I, Jamadi-ol-Aval, Jumada al-Oola, Jamad-el-Ewel, Jumadil Awwal, Djémazi-ul-ewel, Djemazi-ul-evvel, Youmada 1st, Jamadi-es-Sani جمادى الأولى‎
Jumādá al-ākhirah Ǧumādā al-ʾĀḫir, Ǧumādā aṮ-Ṯānī, Iamadi, Jumaada al-Akhir, Jumada al-Akhira, Jumādā al-āḵir, Jumada II جمادى الثاني‎
Rajab Rajah رجب‎
Sha’bān Sha’ban, Sha‘bān, Sha‘ban, Shaaban, Chaban شعبان‎
Ramaḍān Ramadan, Ramadhan, Ramazam رمضان
Shawwāl Shawwal, Shawal شوّال‎
Dhū al-Qa‘dah Dhu'l-Qi'dah, Dhu'l-Qa'dah, Ḏū l-Qaʿdah, Zulqida, Zeekadeh, Zee Radah (typo for Zee Kadah?) ذو القعدة
Dhū al-Ḥijjah Dhu al-Hijjah, Dhu'l-Hijjah, Zulhijja, Zi El-Hidjah, Zil-Hajj ذو الحجة‎

calendar="iranian-persian"

(also known as "Solar Hijri")

The Solar Hijri calendar, or Persian or Iranian calendar, is a solar calendar, whose time reckoning is tied to the Earth's movements around its sun. The Persian calendar is officially used in Iran and Afghanistan.

<date when="1927-06-20" calendar="iranian-persian gregorian">
  <hi rend="italic">Khordad 29, 1306/June 20, 1927</hi>
</date>
<date when="1938-10-09" calendar="gregorian iranian-persian">
  October 9, 1938 (Mehrmah, 17, 1317)
</date>
Month in Iranian/Persian/Solar Hijri Calendar Variant Spellings Persian
farvardin Farvardin, Farvardīn فروردین
ordibehešt Ordibehesht, Ordībehešt اردیبهشت
xordâd Khordad, Khordād خرداد
tir Tir تیر
mordâd Mordad, A-Mordād مرداد
šahrivar Shahrivar, Shahrīvar شهریور
mehr Mehr, Mehrmah مهر
âbân Aban, Ābān آبان
âzar Azar, Āzar آذر
dey Dey دی
bahman Bahman بهمن
esfand Esfand, Espand اسفند

calendar="japanese-nengō"

The Japanese nengō is a periodization system that, during the FRUS timeframe, is based on the reign of Japanese emperors.

<date when="1904-10-02" calendar="japanese-nengō gregorian">
  the 10th day of the 2nd month of the 37th year of Meiji (1904)
</date>
<date when="1905-12-22" calendar="japanese-nengō chinese-era chinese-lunisolar gregorian">
  this 22d day of the 12th month of the 38th year of Meiji, corresponding 
  to the 26th day of the 11th moon of the 31st year of Kuang Hsu 
  (December 22, 1905)
</date>
<date when="1940-10-15" calendar="japanese-nengō gregorian">
  <hi rend="smallcaps">October</hi> 15, 15th Year of Showa (1940)
</date>
Gregorian Year Nengō Emperor Variant and Other Spellings
1772 An'ei Emperor Kōkaku, 1780–1817
1781 Tenmei
1789 Kansei
1801 Kyōwa
1804 Bunka Emperor Ninkō, 1817–1846
1818 Bunsei
1830 Tenpō (also Tenhō)
1844 Kōka Emperor Kōmei, 1846–1867
1848 Kaei
1854 Ansei
1860 Man'en
1861 Bunkyū Bunkin, Bunkiu, Bunion, Bunn-Cue, Boen-Cun,
1864 Genji Gengi
1865 Keiō Ke Yu, Kaiao
1868 Meiji Emperor Meiji, 1868–1912 Miji
1912 Taishō Emperor Taishō, 1912–1926
1926 Shōwa Emperor Shōwa, 1926–1989
1989 Heisei Akihito, 1989–

Source:

calendar="julian"

Reforming the lunar-based Roman calendar, the Julian calendar was solar-based and tied to the Earth's rotation around the sun. Proposed by Julius Ceasar, the Julian calendar was widely used throughout the Roman Empire and in Christian churches and gained dominance in Europe and European-sponsored settlements. While the Gregorian calendar was first introduced in 1582, the Julian calendar was maintained in some countries even through the 1930s. The Julian calendar is still used by the Russian Orthodox Church, the Berber people of North Africa, and on Mount Athos.

<date when="1904-02-16" calendar="julian">
  Russian calendar, February 3, 1904
</date>
<date when="1904-10-30" calendar="julian gregorian">
  October 30/17, 1904
</date>

calendar="korean-era"

Korean dating systems often referred to the reign or era of particular rulers of Korea.

<date when="1901-02-26" calendar="korean-era">
  Fifth year Kwang Mu, February 26
</date>
<date when="1910-06-24" calendar="korean-era">
  Twenty-fourth day of the sixth month of the fourth year of Lyung Heni
</date>
<date when="1894-08-25" calendar="japanese-nengō korean-era korean-lunar gregorian">
  this 26th day of the seventh moon of the five hundred and third year of Ta Chosen 
  [Korea] and the 26th of August of the twenty-seventh year of Meiji [August 25, 1894]
</date>
Reign Personal Name (Westernized) Personal Name (Hangul/Hanja) Courtesy Name, Temple Name, and Other Variants
1724–1776 Yi Geum 이금 (李昑) Gunjin, Songheon, Taejo, Emperor Go
1776–1800 Yi San 이산 (李祘) Hyeongun, Hongjae, Jeongjo
1800–1834 Yi Gong 이공 (李玜) Gongbo, Sunjae, Sunjo
1834–1849 Yi Hwan 이환 (李烉) Muneung, Wonheon, Heonjong
1849–1863 Yi Byeon 이변 (李昪) Doseung, Daeyongjae, Cheoljong
1863–1907 Yi Myeong-bok, Yi Hui 이명복 (李命福), 이희 (李㷩) Seongrim, Juyeon, Gojong, Kojong , Emperor Tae, Gaeguk, Geonyang, Gwangmu, Kwangmu, Kwang Mu, Gwangmuje, Kwangmuje
1907-1910 Yi Cheok 이척 (李坧) Gundang, Jeongheon, Sunjong, Emperor Hyo, Emperor Yunghui, Yunghui, Yunghuije, Yunghŭije, Lyung Heni

Source:

calendar="korean-lunisolar"

Derived from the Chinese calendar, the traditional Korean calendar is a lunisolar calendar.

<date when="1894-08-25" calendar="japanese-nengō korean-era korean-lunar gregorian">
  this 26th day of the seventh moon of the five hundred and third year of Ta Chosen 
  [Korea] and the 26th of August of the twenty-seventh year of Meiji [August 25, 1894]
</date>

calendar="liberian-republic"

Official documents such as treaties may include a parallel date phrase referencing the year of the republic of Liberia.

<date when="1930-04-07" calendar="gregorian liberian-republic">
  this 7th day of April in the Year of our Lord One Thousand Nine
  Hundred and Thirty and of the Republic the Eighty-Third
</date>

calendar="masonic-anno-lucis"

Among the different Masonic calendars, Anno Lucis (A.L. or A:.L:. or the year of light) is used by Freemasons in Scotland, England, Ireland, France, Germany, and the United States. The “year of light” refers to a particular Biblical interpretation of the creation of the world (~4000 BCE).

<date when="1865-06-18" ana="#date_undated-inferred-from-document-content" 
  calendar="masonic-anno-lucis">
  24th day of the 3d month, in the year of light 5865
</date>
<date when="1865-06-10" calendar="masonic-anno-lucis">
  <hi rend="italic">16th day of the 3d month, in the year of light</hi> 5865</date>

calendar="papal-era"

Papal era dates referred to the year in relation to the term of the current Catholic pope.

<date when="1873-05-20" calendar="gregorian papal-era">
  die XX Maii MDCCCLXXIII Pontificatus Nostri anno vicesimo septimo
</date>
<date when="1853-07-29" calendar="gregorian papal-era">
  the 29th day of July, 1853, in the eighth year of our pontificate
</date>

calendar="roman"

The Roman calendar was used by the Roman Kingdom and Roman Republic. Roman dates were referenced by their duration from one of three key days: the nones (fifth or seventh, depending on the length of the month), the ides (the thirteenth or fifteenth of a month), and the kalends (the first of the next month).

<date when="1840-04-27" calendar="roman papal-era gregorian">
  in the year of the incarnation of our Lord, one thousand eight hundred 
  and forty, on the fifth day before the kalends of May (27th April, 1840), 
  in the tenth year of our pontificate
</date>

calendar="rumi"

The Rumi calendar (Rumi takvim), a hsolar calendar based on the Julian calendar but with year one corresponding to 622 A.D., This calendar was used by the Ottoman Empire and its successor, the Republic of Turkey, from 1839 to 1926.

<date when="1909-05-05" calendar="rumi gregorian">
  <hi rend="smallcaps">Nissan</hi>, 21, 1325.<lb/>
  (May 5, 1909.)
</date>
Month Turkish Spelling Variants Ottoman
1 Kânûn-ı Sânî Kanun-i Sani كانون ثانی
2 Şubat Subat شباط
3 Mart مارت
4 Nisan نیسان
5 Mayıs Mayis مایس
6 Haziran حزیران
7 Temmuz تموز
8 Ağustos Agustos اغستوس
9 Eylül Eylul ایلول
10 Teşrin-i Evvel Tesrin-i Evvel تشرین اول
11 Teşrin-i Sânî Tesrin-i Sani تشرین ثانی
12 Kânûn-ı Evvel Kanun-i Evvel كانون اول

calendar="thai-era"

Official documents such as treaties may include a parallel date phrase referring to the year in relation to the 1782 establishment of the Rattanakosin Kingdom (Siam and, later, the Kingdom of Thailand).

<date when="1905-03-31" calendar="thai-era">
  the 31st day of March, Ratanakosindr Sok, 123
</date>

[Note: the 123 above refers to 123rd year of Rattanakosin Kingdom, or 1905]

Reign Name Other Name and Spelling Variants
1782-1809 Rama I Phrabat Somdet Phra Ramathibodi Sri Sinthra, Maha Chakri Boromanat, Phra Phutthayotfa Chulalok the Great
1809-1824 Rama II Phrabat Somdet Phra Ramathibodi Sri Sinthra, Maha Itsarasunthon, Phra Phutthaloetla Naphalai
1824-1851 Rama III Phrabat Somdet Phra Ramathibodi Sri Sinthra, Maha Jessadabodindra, Phra Nang Klao Chao Yu Hua, Phra Maha Jesataraj Chao
1851-1868 Rama IV Phrabat Somdet Phra Paramenthra, Maha Mongkut, Phra Chom Klao Chao Yu Hua
1868-1910 Rama V Phrabat Somdet Phra Paraminthra, Maha Chulalongkorn, Phra Chulachomklao Chao Yu Hua the Great, Phra Piya Maharaj
1910-1925 Rama VI Phrabat Somdet Phra Paramenthra, Maha Vajiravudh, Phra Mongkut Klao Chao Yu Hua, Phra Maha Dhiraraj Chao
1925-1935 Rama VII Phrabat Somdet Phra Paraminthra, Maha Prajadhipok, Phra Pok Klao Chao Yu Hua
1935-1946 Rama VIII Phrabat Somdet Phra Paramenthra, Maha Ananda Mahidol, Phra Atthama Ramathibodin
1946-2016 Rama IX Phrabat Somdet Phra Paraminthra, Maha Bhumibol Adulyadej, Siamindradhiraj Borommanathbobitra, the Great, Somdet Phra Phatthara Maharat
2016-present Rama X Somdet Phra Chao Yu Hua, Maha Vajiralongkorn, Bodindradebayavarangkun

calendar="thai-lunisolar"

The Thai lunar calendar is a Buddhist lunisolar calendar. In 1888, the Thai lunar calendar was replaced by the Thai solar calendar as the legal calendar in Thailand. It is currently used for calculating holy days and other religious and traditional events.

<date when="1879-09-21" calendar="thai-era thai-lunisolar gregorian">
  Sunday, 6 of waxing moon, 11th month, year of Rallit, 1st of the 
  decade, 1241 of civil era, corresponding to September 21, 1879, 
  of Christian era</date>

calendar="tibetan-phugpa"

Introduced in 1447, the lunisolar Tibetan phugpa calendar is modified from Indian calendar systems and based on the Kālacakra Tantra. In the phugpa calendar, each year is associated with an element and an animal; pairings recur in 60-year cycles.

Order Element Aspect
1 Fire male
2 Fire female
3 Earth male
4 Earth female
5 Iron male
6 Iron female
7 Water male
8 Water female
9 Wood male
10 Wood female
Order Animal
1 Rabbit
2 Dragon
3 Snake
4 Horse
5 Goat
6 Monkey
7 Rooster
8 Dog
9 Pig
10 Rat
11 Ox
12 Tiger
<date when="1943-02-17" calendar="tibetan-phugpa gregorian">
  13th Day of 1st month, Water Sheep Year. (Corresponding to February 1943.)
</date>
<date when="1947-10-09" calendar="tibetan-phugpa gregorian">
  25th of 8th month Fire-Pig Tibetan Year [1947]
</date>

calendar="us-republic"

Official documents such as treaties may include a parallel date phrase referring to the year in relation to the independence of the United States (1776).

<date when="1888-01-16" calendar="gregorian us-republic">
  this 16th day of January, in the year of our Lord one thousand eight hundred 
  and eighty-eight, and of the independence of the United States the one 
  hundred and twelfth</date>
<date when="1941-05-28" calendar="gregorian us-republic">
  this 28th day of May, in the year of our Lord nineteen hundred and forty-one, 
  and of the Independence of the United States of America the one hundred and 
  sixty-fifth</date>