Departments
Intermediate Japanese - Free Online Course
GENGŌ
元号
imperial date system
In Japan, the years are measured according to two systems. The first is the Western calendar system based on decades and centuries. The second is the imperial-reign-based system, which measures the current year from the beginning of the sitting emperor’s reign. The imperial date system was imported from China during the seventh century, and made official during the reign of Emperor Meiji (1868-1912). Even today, the imperial dates are mandatory on many official documents.
Under the imperial date system, the year 2006 would be Heisei 18 / 平成十八年. The Heisei era began when the emperor Akihito took the throne (following the death of his father, Hirohito—the Emperor Shōwa) on January 8, 1989. The year 1989 was therefore Heisei 1, or heisei gannen平成元年. Similarly, the year 1987 was Shōwa 62, or the sixty-second year of the reign of the Emperor Shōwa.
Japanese Emperors effectively have two names—a personal name, as well as a “reign name.” The reign name is chosen based on the particular theme or priorities that that a new emperor wants to focus on during his reign. Below are some recent emperors with their reign names.
Emperor
Reign Name
Reign Name Meaning
Duration of Reign
Akihito
Heisei
“Peace Achieved”
1989 -
Hirohito
Shōwa
“Enlightened Peace”
1926-1989
Yoshihito
Taishō
“Great Righteousness”
1912-1926
Mutsuhito
Meiji
“Enlightened Rule”
1868-1912
Contrary to what one might expect, the existence of two date systems does not cause confusion when referring to dates. All Japanese can deal competently with both systems.