From ancient times in Asia,
it was the practice to count years according to the reign of an emperor.
This custom of reckoning years by eras was adopted in Japan in seventh century.
From that time until the nineteenth century,
the reigning emperor decided when one era ended and another began.
Under the current system,
adopted following the ascension of Emperor Meiji in 1868,
the era begins on the day an emperor ascends the throne
and continues until his death.
Thus Meiji era began in 1868 and lasted until 1912.
Showa began in 1926 when Emperor Hirohito ascended and lasted until 1989.
At present, the era is Heisei.
Meiji : 1868/ 9/ 8 - 1912/ 7/30
Taisho : 1912/ 7/30 - 1926/12/25
Showa : 1926/12/25 - 1989/ 1/ 7
Heisei : 1989/ 1/ 7 -
Actually, any date of the year during which era has changed,
could be referred in either era.
For example, 1989/1/5 could be referred as Heisei 1st 1/5 as well.
Era changes at 12:00 noon so eras do not overlap in terms of hours
although it does in terms of day.
- to be added -
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