One of the more interesting, and still commonly-used practices, in Japanese culture is the use of imperial reigns in place of years in the Gregorian calendar. This is most often used now when talking about generations or one’s birth year, whereas the Gregorian calendar is often used for other historical discussions or other such situations.
Prior to the Meiji Emperor, Japan used since antiquity a system where eras were frequently proclaimed especially after major events, disasters, etc. For example, Emperor Juntoku reigned from 1210 to 1221, but within that reign he proclaimed 4 eras:
- Jōgen (承元, 1207–1211)
- Kenryaku (建暦, 1211–1213)
- Kempō (建保, 1213–1219)
- Jōkyū (承久, 1219–1222)
The founder of Jodo Shu Buddhism, Honen was said to have died in the 2nd year of Kenryaku which maps to 1212 in the Western calendar. The 260+ year late-medieval Edo Period had more than 40 different era names within it (see Wikipedia for details).
However, this system completely changed with the reign of the Meiji Emperor ō (reign 1867 – 1912). The system was simplified such that each emperor had a *single* reign name, starting with the Meiji Emperor. Since then, there have 5 emperors total, and 5 reigns accordingly:
- Meiji (明治, 1868 – 1912)¹
- Taishō (大正, 1912 – 1926)
- Shōwa (昭和, 1926 – 1989)
- Heisei (平成, 1989 – 2019)
- Reiwa (令和, 2019 – present)
So, nowadays, when people in Japan talk about what year they were born, they might say “the 52nd year of Shōwa” or in Japanese shōwa go-jū-ni nen.
This also comes up a lot when people joke about different Japanese generations. My wife and I are born in the 1970’s, so we are “Showa” generation kids, by my kids who are half-Japanese are “Heisei” kids. Nowadays, there are even “Reiwa” generation kids now.
On TV documentaries and other sources, reign years are also frequently used alongside the Western calendar, so you get used to doing the math like so:
- The first year of an Emperor is year 1, not year 0.
- So, for example Heisei 3 is 1991 (1989 + 3 – first year of reign).
- Shōwa 47 would be 1926 + 47 – first year of reign, or 1972.
Interestingly, Japan is not the only culture to have novel calendar systems based on the dates of rulers. Rome during the Republic had its own system. The ancient Roman calendar was confusing and imprecise until Julius Caesar fixed it in 46 BCE. However, in popular Roman culture, people told dates based on who the two elected consuls were that year. Just as Japanese know who the line of Emperors are in recent times (see above), Romans in those days remembered each year.
One might say something like “April 4th in the year that Pompey and Crassus were consuls” or “when Caesar and Bibulus were consuls” or something like that.
I often find these little cultural oddities interesting because they add “flavor” to a culture even if they’re not entirely practical. The Julian Calendar introduced by Caesar was a huge improvement over the old system, but I wonder if a little something also got lost in the process too. 😀
¹ Emperor Meiji reigned starting in 1867, but due to radical changes in Japan at the time, it wasn’t technically formalized until 1868.
Gleanings in Buddha-Fields 
