Gengō means regnal year or era name, a name for years of the reign of a sovereign rule. Regnal years are considered ordinal numbers and not cardinal numbers, therefore, there is a first year of rule, but no “year zero” of rule. In Japan, both western years based on the Gregorian Calendar and Japanese years based on Gengō are still used nowadays. Therefore, you will see and hear this year referred to as either 2025 or Reiwa (令和)7, meaning the 7th year of Reiwa, or both in Japan.
History of Gengō
It is said that the Gengō was originated in China as Nengō (年號nianhao: era names) circa 140 BC by Wu Dai (武帝 Emperor Wu) in the Han (漢) dynasty. Since then, it has been used to indicate the length of the reign of each Emperor until the Shingai Kakumei (辛亥革命Xinhai Geming: Xinhai Revolution) ended the imperial system in 1912. In Japan, as is often the case with many things imported from China, especially since the mid-6th century, the Gengō system was introduced and adopted by Emperor Kōtoku (孝徳天皇 Kōtoku Tennō) in 645 AD and the designated Gengō was Taika (大化). The system was in use sporadically from 645 and has been in use since 701 to the present. However, it was common to change Gengō during the reign of an Emperor for various reasons. For example, when a vicious epidemic breaks out, an Emperor decides to change Gengō so that the epidemic would subside with the by-gone ominous Gengō. On another occasion, an Emperor might listen to the prayers or rituals of an Onmyōji (陰陽師 a master of yin-yang divination or a spiritual specialist in ancient Japan)and would follow the advice by the Onmyōji by changing the inauspicious Gengō.
Current practice of Gengō
Since the Meiji period (1868-1912), the “one reign, one Gengō (era name)” system has been introduced by the Meiji government so only one Gengō has been used by each emperor. Therefore, each emperor has been known posthumously by the emperor’s era name. Incidentally, the emperor and empress are the only people in Japan throughout history who don’t have their family name. They only have their first names with their imperial title. For example, the current emperor is called Emperor Naruhito (徳仁天皇 Naruhito Tennō) and the current empress is called Empress Masako (雅子皇后 Masako Kōgō). Other imperial family members, such as Akishino-no-miya (秋篠宮 Emperor’s younger brother), are called by their imperial household/family branch such as Prince Akishino branch of the Imperial Family. In addition, you are not supposed to call or refer to the current emperor with Gengō like Emperor Reiwa (Reiwa Tennō). As mentioned above, we can call or refer to deceased emperors with their Gengō posthumously such as Meiji Tennō, Taishō Tennō and Shōwa Tennō. The former emperor, Akihito (明仁), who reigned in the Heisei era (平成時代 Heisei jidai) and abdicated the throne, is now referred to as the Emperor Emeritus (上皇 Jōkō), and his wife, Michiko (美智子), is now referred to as the Empress Emerita (上皇后 Jōkōgō). Then, how do we call or refer to the current emperor? You may call or refer to him as Kinjō Tennō (今上天皇 the reigning/current Emperor).
Recording the beginning of an era
There are two ways to record the beginning of an era, Kigen (紀元). One is to designate a certain year as the beginning and count the number in an infinite way. For example, the origin of Western eras mark the starting year as the first year of BC (Before Christ) like BC123 or BCE (Before Common Era) like BCE456. Likewise, AD (Anno Domini) like AD789 or CE (Common Era) like CE321 are used to mark the starting year. Japan also has its own way of counting the beginning of an era. According to records, the origin of Japan is considered to be 660 BC when Emperor Jinmu (神武天皇 Jinmu Tennō) allegedly had his accession. It is called Kōki (皇紀 imperial calendar) and the year 2025 is Kōki 2685. By adding 660 to the western calendar, you can count the number of Kōki years. However, this Kōki calendar method is not widely used in Japan any more.
Usage of Gengō
Another way to designate a certain year as the beginning and count the number in a finite way is using the Gengō system. In that sense, it is a unique method to record a certain era. As mentioned above, historically, any number of Gengō was used during a certain emperor’s reign, but “one reign, one Gengō” is the norm now since the Meiji period (明治時代 Meiji jidai). It is common practice that once a certain Gengō is used, the same Gengō won’t be used again. In the past, some Gengō were made up with more than two Kanji (漢字 Chinese characters), but it is common that Gengō consists of only two Kanji. It is widely acknowledged that Kanji with auspicious meanings are chosen to make up two-Kanji compounds.
The current Gengō
The current era is called Reiwa (令和) and was inaugurated on the 1st of May in 2019. Since the inaugurated year is the first year, Gannen (元年) of the Gengō, it is the 7th year of Reiwa this year. The current reigning emperor, Kinjō Tennō (今上天皇) is Naruhito (徳仁). It is commonly acknowledged that Kinjō Tennō is the 126th Tennō in his lineage.
Author
Shunichi Ikeda
BAS Hons (ANU)
MEd (SUNY at Buffalo)
Visiting Fellow, ANU College of Asia and the Pacific
