Japanese Dating Systems for Coinage
For the machine-struck coinage of Japan (1870 to date), the dating of the coinage has been for the most part based off the reigning year of the emperor. Beginning with the coinage of 1870, the date that was stamped on the coins was the Japanese character combination for Meiji (enlightened peace), denoting Emperor Mutsuhito.
For the Japanese Occupation Coinage of World War II, a different dating system and dates appear on the coinage. The Japanese Shinto Dynastic Calendar starts with the year zero, equating to 660 BCE – this is the year Japan is believed to have been founded. For the coinage struck by the Osaka Mint for use in the East Indies under Japanese occupation, the dates 2603 and 2604 were used and equate to 1943 and 1944 in the Common Era calendar.
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