The upper left shows the Rumi date in Ottoman Turkish: year 1327, 7 Nisan (٧ نیسان ١٣٢٧)
The same Julian date (7 April, ΑΠΡΙΛΙΟΣ 7) and day (Thursday, Πέμπτη) appears below in Greek with the AD year 1911
Next to that is the Gregorian date (20 April, AVRIL 20) and day (Jeudi) in French
Above these two is 30 (twice), the number of days in the Julian and Gregorian months; the month (April, Априлий) and day (Thursday, Четвъртъкъ) in Bulgarian
Under the Greek is Armenian, reading April (ԱՊՐԻԼ) and Thursday (ՀԻՆԳՇԱԲԹԻ)
The upper right shows the Islamic date21 Rebiülahir 1329 (٢١ ربيع الآخر ١٣٢٩)
The Hebrew date 22 Nisan 5671 (22 ניסן 5671) appears at the bottom.
In the Islamic state of the Ottoman Empire, the religious Islamic calendar (a lunar calendar) was in use. In this calendar, months coincide with lunar phases. Because a "lunar year" (the combined duration of twelve lunar phases) is shorter than the solar year, the seasons cycle through the lunar months as the solar years pass. "As a result," says the Astronomical Almanac, "the cycle of twelve lunar months regresses through the seasons over a period of about 33 [solar] years".[1][a]
1677 Introduction of the Fiscal calendar
In 1677, Head Treasurer (Ottoman Turkish: باش دفتردار, Baş Defterdar) Hasan Pasha under Sultan Mehmed IV proposed the correction of financial records by dropping one year (an escape year) every 33 years, resulting from the difference between the lunar Islamic calendar and the solar Julian calendar.[2]
In 1740 (1152 AH) during the reign of Sultan Mahmud I, March was adopted as the first month of the fiscal year for the payment of taxes and dealings with government officials instead of Muharram following Treasurer Atıf Efendi's proposal.[2]
Proposed by Treasurer Moralı Osman Efendi during the reign of Sultan Abdul Hamid I, the range of the fiscal calendar applications was extended in 1794 to state expenditures and payments in order to prevent surplus cost arising from the time difference between the Islamic and Julian calendar.[2]
1840 Adoption of the Julian Calendar
The Julian calendar, used from 1677 AD on for fiscal matters only, was adopted on March 13, 1840 AD (March 1, 1256 AH), in the frame of Tanzimat reforms shortly after the accession to the throne of Sultan Abdülmecid I, as the official calendar for all civic matters and named "Rumi calendar" (literally Roman calendar).[2] The counting of years began with the year 622 AD, when Muhammad and his followers emigrated from Mecca to Medina, the same event marking the start of the Islamic calendar. The months and days of the Julian calendar were used, the year starting in March.[3] However, in 1256 AH the difference between the Hijri and the Gregorian calendars amounted to 584 years. With the change from lunar calendar to solar calendar, the difference between the Rumi calendar and the Julian or Gregorian calendar remained a constant 584 years.
1917 Adoption of the Gregorian calendar
Since the Julian to Gregorian calendar changeover was finally being adopted in neighboring countries, the Rumi calendar was realigned to the Gregorian calendar in February 1917, leaving the difference of 584 years unchanged, however. Thus, after February 15, 1332 AH (February 1917 AD), the next day instead of being February 16 suddenly became March 1, 1333 AH (March 1, 1917 AD).[4] The year 1333 AH (1917 AD) was made into a year with only ten months, running from March 1 to December 31. January 1, AD 1918 thus became January 1, AH 1334.[5] The Rumi calendar remained in use after the dissolution of the Ottoman Empire into the first years of the succeeding Republic of Turkey.
1925 Discontinuation of the Rumi calendar
The use of the AH era was abandoned as part of Atatürk's reforms by an act of December 26, 1341 AH (1925 AD) and was replaced by the Gregorian year from 1926.[6]
Calendar months
The names of four months that occur in pairs in the Semitic/Arabic naming system (Teşrin-i Evvel, Teşrin-i Sânî and Kânûn-ı Evvel, Kânûn-ı Sânî) were changed on January 10, 1945 to Turkish language names, Ekim, Kasım, Aralık and Ocak, for simplicity. From 1918 the fiscal year has commenced on 1 January. The other months' names were from the Syriac language, except for Mart, Mayıs, and Ağustos, which were derived from Latin.
Rumî calendar months
Month
Fiscal year
Turkish
Ottoman
Days
Notes
1
11th month
Kânûn-ı Sânî
كانون ثانی
31
İkinci Kânûn (2nd Kânûn)
2
12th month
Şubat
شباط
28 or 29
3
1st month
Mart
مارت
31
4
2nd month
Nisan
نیسان
30
5
3rd month
Mayıs
مایس
31
6
4th month
Haziran
حزیران
30
7
5th month
Temmuz
تموز
31
8
6th month
Ağustos
اغستوس
31
9
7th month
Eylül
ایلول
30
10
8th month
Teşrin-i Evvel
تشرین اول
31
Birinci Teşrin (1st Teşrin)
11
9th month
Teşrin-i Sânî
تشرین ثانی
30
İkinci Teşrin (2nd Teşrin)
12
10th month
Kânûn-ı Evvel
كانون اول
31
Birinci Kânûn (1st Kânûn)
1917 Conversion Table
In 1917 (1332-1333), a major calendar reform aligned the Rumi calendar with the Gregorian calendar. This table, adapted from the work of Richard B. Rose, lists the equivalent dates for that year.[7]
^This means that there are 34 Hijri years to 33 Gregorian years.
References
^Richards, E. G. (2012). "Calendars"(PDF). In Urban, Sean E.; Seidelmann, P. Kenneth (eds.). Explanatory Supplement to the Astronomical Almanac. Mill Valley, CA: University Science Books. p. 606. ISBN978-1-891389-85-6. Archived from the original(PDF) on 30 April 2019.
