Japanese era name facts for kids

The Japanese era name (Japanese: 年号, Hepburn: nengō, "year name") or gengō (元号) is a special way to count years in Japan. It's like saying "the year of King Arthur" or "the year of the first moon landing." In Japan, each time a new emperor starts ruling, a new era name begins. For example, the current era is called Reiwa.

This system started in Imperial China a long, long time ago, around 140 BCE. Japan adopted it in 645 AD. While other countries like China and Korea also used era names, Japan is the only one that still uses them officially today. You'll see these era names on official papers and in government offices.

Since 1868, Japan has used a simpler system: one emperor, one era name. This means the era name only changes when a new emperor takes the throne. The five era names since 1868 are Meiji, Taishō, Shōwa, Heisei, and Reiwa. You can even shorten them! For example, S55 means Shōwa 55 (which was 1980). The Shōwa era was the longest, lasting over 62 years.

The newest era, Reiwa (令和), began on May 1, 2019. This was when Naruhito became the 126th Emperor of Japan. His father, Akihito, was the first emperor in a long time to step down from his role instead of ruling until his death. The Reiwa era followed the Heisei era, which had lasted 31 years.

Understanding Japanese Era Names

Keizō Obuchi, a government official, announcing the new era name "Heisei" in 1989.

Yoshihide Suga, another government official, announcing the "Reiwa" era name in 2019.

A Japanese calendar from 1729, showing how era names were used.

The idea of Japanese era names came from China in 140 BC. Japan started using them in 645 AD, during the time of Emperor Kōtoku.

The very first era name was "Taika." It celebrated big political changes happening in Japan at that time. The system stopped for a bit in the late 600s but was brought back for good in 701 during Emperor Monmu's rule. Since then, era names have been used continuously.

How Era Names Changed in the Past

Before the Meiji period (which started in 1868), era names changed quite often. A new era name was usually announced within a year or two after a new emperor started his reign. Sometimes, new era names were chosen because of special events or even natural disasters. For example, the "Wadō" era started because copper was discovered in a place called Chichibu.

Most era names are made up of two kanji (Japanese characters). For a short time during the Nara period, some names had four characters, like "Tenpyō Kanpō." Since the Heian period, many era names have been chosen to reflect Confucian ideas, which are ancient Chinese philosophies.

There have been 248 Japanese era names in total. Only 73 different kanji characters have been used to create them. Most era names lasted less than 10 years. Only a few, like Heisei and Shōwa, lasted more than 30 years.

Era Names in Modern Japan

When Mutsuhito became emperor in 1867, the era name was "Keiō." But on October 23, 1868, it changed to "Meiji." This is when the "one reign, one era name" system began. This means that an era name now only changes when a new emperor takes the throne.

In modern Japan, the first year of a new era starts right when the new emperor begins his rule and ends on December 31st of that year. After that, the years follow the Gregorian calendar (our usual calendar). For example, the Meiji era lasted until July 30, 1912, when the emperor died. So, 1912 was known as both "Meiji 45" and "Taishō 1."

This "one reign, one era name" rule became an official law in 1979. So, since 1868, there have only been five era names: Meiji, Taishō, Shōwa, Heisei, and Reiwa. Each one belongs to just one emperor. After an emperor dies, he is usually referred to by the name of his era. For example, Mutsuhito is known as "Emperor Meiji."

It's important to know that in Japan, people usually call the current emperor "His Majesty the Emperor" or "current emperor." It's not polite to call the current emperor by the current era name (like "Reiwa"), because that will be his name after he passes away. Also, using the emperor's given name (like "Naruhito") is very rare and considered impolite in Japanese culture.

When Akihito stepped down as emperor on April 30, 2019, a new era name was needed. The new name, Reiwa, was announced on April 1, 2019.

Periods Without Official Era Names

The era name system wasn't always used continuously. After Emperor Kōtoku died, no era names were used between 654 and 686. Emperor Tenmu brought the system back briefly in 686, but it stopped again when he died. Finally, in 701, Emperor Monmu started the era name system again, and it has continued without stopping ever since.

Even when there weren't official era names, people still needed to refer to years. So, they would identify years by the emperor's reign. For example, the year 572, when Emperor Bidatsu became emperor, was called "the first year of Emperor Bidatsu."

Unofficial Era Names

Besides the official era names chosen by the imperial court, there were also unofficial era names. These were called shinengō (meaning "personal era names"). You can sometimes find these unofficial names in old documents from shrines and temples. Most of these unofficial names are from the middle ages.

It can be tricky to know exactly when these unofficial names were used because official records are missing. For example, the unofficial name "Hakuhō" might refer to different periods depending on the document. These unofficial names could be used as an alternative way to date periods when there was no official era name.

Some other well-known unofficial era names include "Hōkō" (591–621+ CE) and "Suzaku" (686). The most recent unofficial era name was "Seiro" (1904–1905), which was named after the Russo-Japanese War.

Software Support for Era Names

Computers and software need to understand Japanese era names, especially when a new era begins. For example, when the Reiwa era started on May 1, 2019, software companies had to update their systems.

Special characters are even assigned to some era names in computer systems like Unicode. For instance, ㋿ is a special character for the Reiwa period.

Many computer programs and calendar apps also support converting dates to and from the Japanese era system.

How to Convert Japanese Era Years

To figure out what a Japanese era year is in the Gregorian calendar (our common calendar), you need to know the first year of that Japanese era.

Here's the simple math:

1. Find the starting year of the Japanese era name.
2. Add the Japanese year number to that starting year.
3. Subtract 1.

For example, if the Meiji era started in 1868, and you want to know what Meiji 45 is: 1868 (start year) + 45 (Meiji year) - 1 = 1912. So, Meiji 45 is 1912.

List of Japanese Era Names

The system of Japanese era names began in 645 AD. After 701, era names were used continuously. As of April 1, 2019, there have been 239 era names!

Asuka period

Nara period

Heian period

Kamakura period

Nanboku-chō period

During this time, there were two imperial courts, so there were two sets of era names.

Southern Court

Northern Court

Muromachi period

Azuchi–Momoyama period

Edo period

Modern Japan

Since 1868, Japan has used the "one reign, one era name" system.

Images for kids

See also

• Calendar
• Japanese calendar
• Japanese imperial year
• Jikkan Jūnishi (sexagenary cycle)
• Regnal name
• Regnal years worldwide
• Related systems:
  • Chinese era name
  • Korean era name
  • Vietnamese era name