Japanese calendar. Emperors and their reigns
Although the Gregorian calendar has been in use in Japan since January 1, 1873 AD to the present day, the Japanese calendar is also widely used. The Japanese calendar is used, in particular, on Japanese coins and bank notes.
The main feature of the Japanese calendar is: it is divided into the eras, coinciding with the reigns of this or that emperor. For instance, 1980 AD falls on Showa’s 55th year, whereas 2013 AD falls on Heisei’s 25th year.
Let’s take a look at the structure of the year inscription in the Japanese calendar on the following example:
1 — name of the era (on this piece: 平成, Heisei);
2 — the number of years elapsed since the beginning of the era up to the current year (on the image specified, that is: 二十二, 22);
3 — character «Nen», 年, translated as «the year».
Japanese coins minted in the beginning of the XX-th century are known to carry date inscriptions written and read from right to left. So, in general, if you see the character «Nen», this tells you that it is the end of the line and hence you should be reading it the other way around. Eras are always first, followed by the number of years and then lastly the character «Nen».
As stated above, each Japanese era begins with the first year of government of the new Japanese emperor. Hence, in order to recognize the Japanese date, we have to know the name of the era and exact year in which the reign started. Here is the table that includes all the necessary information:
|Name of the era
and emperor’s name
|The year when
the reign started
|Motto of the regency
|| Meiji (Mutsuhito)
|| Taishō (Yoshihito)
|| Shōwa (Hirohito)
|| Heisei (Akihito)
After comparing emperor’s character combination on the example and in the table above, we can define the Emperor. In our picture, this is Heisei. Hence, the era of interest began in the year 1989 AD.
The next step is identifying the current year of the Emperor’s reign. In some cases the date is written with Arabic numerals, e.g. 昭和54年, but in all the other cases it’s necessary to be able to recognize the original Japanese numerals. These symbols are available in the converter on the lefthand side of this page.
Keep in mind the following: if the character of any digit from «1» to «9» is located in front of the symbol «10» or «100» (to the left of either «10» or «100»), this digit stands for the number of tens or hundreds (the digit is a multiplier). Otherwise (if the digit is located to the right of the tens or hundreds symbol), this digit is a unit of a year’s number. In our case, the year of the era is 2×10 + 2 = 22.
The final calculation in the algorithm is: you should sum the year in which the reign started and current year specified on the coin, and afterwards subtract 1 year (since the eras start from 1, not 0). Getting back to our example: 1989 + 22 – 1 = 2010.
Let us now summarize what we know about the manual Japanese year calculation algorithm:
1) Among all the characters find the date inscription;
2) Find the character «Nen», go to the opposite end of the date, find the first two symbols, find the corresponding emperor, refer to the table and put down the year in which this emperor started his rule;
3) Decipher the current year of the reign from the characters that are left;
4) Make use of the final calculation algorithm.
Again, keep in mind that Japanese characters may be written in the reverse order, i.e. from right to left (in this case the character «Nen» (年) is first in the date inscription). In the direct order of characters the symbol «Nen» comes last.
There's a peculiarity concerning the years 1989, 1926 etc., in other words, the first year of the Emperor's rule. Japanese dates in those cases include 元, which means «the first» (ordinal numeral), but not 一 («one», cardinal numeral). For example, 1989 (the 1st year of Akihito's rule) goes like 平成元年, but NOT 平成一年.
As a part of a typeface, Japanese numerals from 1 to 10, as well as «100», are written as follows:
As stated in the converter, the year zero of the corresponding era (applied to the date on those coins) was 660 B.C. — the year when Japan is believed to have been founded. These dates are taken from the Japanese Shinto dynastic calendar. These issues were struck for use in the Netherlands East Indies (another name is the Dutch East Indies), not for internal circulation. The Dutch East Indies was the Dutch colony that became modern Indonesia following World War II — in 1945, when Indonesian nationalists declared independence after the period of the Japanese occupation. This picture (source) shows the growth of territory of the Netherlands East Indies during XVIII–XX centuries, and this piece of the world political map shows both Japan and Indonesia, so that you can understand the distance between them.
The following issues were struck at the Osaka Mint. The only inscription (written in Japanese characters) found on these coins is “Dai Nippon” standing for “Great Japan”. The war situation had worsened to the point that shipping the coins to the destination point, i.e. the Netherlands East Indies, became virtually impossible. Consequently, almost the entire issue — from 69 to 233 million coins, depending on the coin type — was lost or remelted at the mint. So this is why these occupation coins are relatively rare and have a high market value.
The following types of Japanese occupation coins for the Dutch East Indies are known:
▪ 1 sen, aluminium, struck in 2603 (1943 AD) and 2604 (1944 AD);
▪ 5 sen, aluminium, struck in 2603 (1943 AD);
▪ 10 sen, tin alloy, struck in 2603 (1943 AD) and 2604 (1944 AD).
This is what they look like:
1 sen, aluminium, 2604 (1944 AD)
10 sen, tin alloy, 2604 (1944 AD)
Dating coins issued for the puppet state of Manchukuo by Japan in between 1932 and 1945 AD
Ìanchukuo (this is its map, Manchukuo coloured green and partly outlined) was a puppet state formed by the Japanese military administration in the occupied territory of Manchuria and eastern Inner Mongolia, these regions are located in Northern China. This puppet state was established on March 1, 1932 and ceased on August 19, 1945.
The monetary unit of Manchukuo was the ‘Chiao’ (an alternative spelling is ‘jiao’). 1 chiao = 10 fen = 100 li.
Puyi (or in full ‘Aisin-Gioro Puyi’), the last Qing emperor, was installed as the nominal regent and emperor of Manchukuo. A photograph of Puyi is shown on the right. During 1932–1934 Puyi had the title of Supreme Ruler, while the era name was called 大同 (Ta T'ung, or Datong). During 1934–1945 his title was Emperor, and the era name was called 康碲 (K'ang Te, or Kangde).
The date was usually specified on the lower part of the obverse side of the coin. Keep in mind that all inscriptions were made right to left.
Ta T'ung period dating (1932–1934)
K'ang Te period dating (1934–1945)
In the picture below you can see a coin (made of bronze) issued for the puppet state of Manchukuo. The face value of this coin is 1 fen (壹分), it was minted in 1934 AD, in the 3rd year of the reign of Puyi as the Supreme Ruler (大同).
Thus, the full hieroglyphic inscription of the year specified on the coin is as follows: 年三同大. Manchukuo state coins can be easily recognized by the typical image of the flag of Manchukuo depicted on their obverses. In colour the flag of the Manchukuo state looks like this:
Japanese monetary denominations
The Japanese yen is the official currency of Japan. 1 yen is divided into 100 sen. Since 1954 small coins are no longer in use. The current series of Japanese bank notes range from 1,000 to 10,000 yen. Currently, 6 denominations of Japanese coins are in circulation, viz. 1, 5, 10, 50, 100 and 500 yen.
The inscriptions of the yen and the fractional Japanese currency (that are no longer in use) are as follows:
1 yen — 円 — the main currency unit; first appeared in 1871, still in circulation.
1 sen — 銭 — 1/100th of a yen; went out of circulation on January 1, 1954.
1 rin — 厘 — 1/10th of a sen; went out of circulation on January 1, 1954.
Converter updates and bugfixes.
Update @October 26, 2010, concerning the years when one emperor died and the next one became the new emperor (years 1912, 1926 and 1989 in the reverse computation): the output hieroglyphic year is now displayed as both the last year of the previous emperor and the first year of the new emperor.
Updates @January 1, 2011: the direct converting input data processor has been updated: it is now possible to enter only one era at a time; if the incorrect ordinal year of rule is entered, i.e. if the year is greater than the emperor had really governed, the following error message appears: «The year of rule you've entered is incorrect!»; fixed the bug of misuse of the symbols «元» and «一», now they are shown only in appropriate cases.
Update @April 25, 2011: now converter supports Japanese occupation coins struck at the Osaka Mint for Dutch East Indies during WWII.
Update @April 29, 2011: guide for dating coins issued by Japan for the puppet state of Manchukuo in between 1932 and 1945 AD has been added into the descriptive part.
Update @September 15, 2013: description of the first year of emperor's rule on Japanese coins.