The or, is the first of the two elements that identify years in the Japanese era calendar scheme. The second element is a number which indicates the year number within the era (with the first year being ""), followed by the literal "" meaning "year".
Era names originated in 140 BCE in Imperial China, during the reign of the Emperor Wu of Han.[1] [2] As elsewhere in the Sinosphere, the use of era names was originally derived from Chinese imperial practice,[3] [4] although the Japanese system is independent of the Chinese, Korean, and Vietnamese era name systems. Unlike its other Sinosphere counterparts, Japanese era names are still in official use. Government offices usually require era names and years for official papers.
The five era names used since the end of the Edo period in 1868 can be abbreviated by taking the first letter of their romanized names. For example, S55 means Shōwa 55 (i.e. 1980), and H22 stands for Heisei 22 (2010). At 62 years and 2 weeks, Shōwa is the longest era to date.
The [5] era began on 1 May 2019, the day of accession of Naruhito to the throne as the 126th Emperor of Japan,[6] following the day of the planned and voluntary abdication[7] of his father, the 125th Emperor, Akihito. Emperor Akihito had received special permission to abdicate,[8] rather than serving in his role until his death, as is the rule.[9] The era followed the 31st and final year of the, which had started on the day after the death of Emperor Hirohito on 8 January 1989.
The system on which the Japanese era names are based originated in China in 140 BC, and was adopted by Japan in 645 AD, during the reign of Emperor Kōtoku.
The first era name to be assigned was, celebrating the political and organizational changes which were to flow from the great of 645. Although the regular practice of proclaiming successive era names was interrupted in the late seventh century, it was permanently re-adopted in 701 during the reign of Emperor Monmu (697–707). Since then, era names have been used continuously up through the present day.
Prior to the Meiji period, era names were decided by court officials and were subjected to frequent change. A new era name was usually proclaimed within a year or two after the ascension of a new emperor. A new era name was also often designated on the first, fifth and 58th years of the sexagenary cycle, because they were inauspicious years in Onmyōdō. These three years are respectively known as kakurei, kakuun, and kakumei, and collectively known as sankaku. Era names were also changed due to other felicitous events or natural disasters.
In historical practice, starts whenever the emperor chooses; and the first year continues until the next lunar new year, which is understood to be the start of the nengō's second year.[10]
Era names indicate the various reasons for their adoption. For instance, the nengō, during the Nara period, was declared due to the discovery of copper deposits in Chichibu. Most nengō are composed of two kanji, except for a short time during the Nara period when four-kanji names were sometimes adopted to follow the Chinese trend.,, and are some famous nengō names that use four characters. Since the Heian period, Confucian thoughts and ideas have been reflected in era names, such as, and . Although there currently exist a total of 248 Japanese era names, only 73 kanji have been used in composing them. Out of these 73 kanji, 31 of them have been used only once, while the rest have been used repeatedly in different combinations.
The vast majority of Japanese Era Names were used for less than 10 years, with two being used for less than a year. Only 28 have been used for more than 10 years and less than 30 years. Only Heisei, Oei, Meiji, and Showa have been used for more than 30 years.
Mutsuhito assumed the throne in 1867, during the third year of the era. On 23 October 1868, the era name was changed to, and a system was adopted, wherein era names would change only upon immediate imperial succession. This system is similar to the now-defunct Chinese system used since the days of the Ming dynasty. The Japanese nengō system differs from Chinese practice, in that in the Chinese system the era name was not updated until the year following the emperor's death.
In modern practice, starts immediately upon the emperor's accession and ends on 31 December. Subsequent years follow the Gregorian calendar. For example, the Meiji era lasted until 30 July 1912, when the Emperor died and the era was proclaimed. 1912 is therefore known as both "Meiji 45" and, although Meiji technically ended on 30 July with Mutsuhito's death.
This practice, implemented successfully since the days of Meiji but never formalized, became law in 1979 with the passage of the . Thus, since 1868, there have only been five era names assigned: Meiji, Taishō, Shōwa, Heisei, and Reiwa, each corresponding with the rule of only one emperor. Upon death, the emperor is thereafter referred to by the era of his reign. For example, Mutsuhito is posthumously known as . It is protocol in Japan that the reigning emperor be referred to as or . To call the current emperor by the current era name, i.e. "Reiwa", even in English, is a faux pas, as this is – and will be – his posthumous name. Use of the emperor's given name (i.e., "Naruhito") is rare, and is considered vulgar behaviour in Japanese.
The Emperor Akihito abdicated on 30 April 2019, necessitating a change in nengō. The new name, made public on the morning of 1 April of the same year, is .
The era name system that was introduced by Emperor Kōtoku was abandoned after his death; no era names were designated between 654 and 686. The system was briefly reinstated by Emperor Tenmu in 686, but was again abandoned upon his death about two months later. In 701, Emperor Monmu once again reinstated the era name system, and it has continued uninterrupted through today.
Although use of the Gregorian calendar for historical dates became increasingly common in Japan, the traditional Japanese system demands that dates be written in reference to era names. The apparent problem introduced by the lack of era names was resolved by identifying the years of an imperial reign as a period.[11]
Although in modern Japan posthumous imperial names correspond with the eras of their reign, this is a relatively recent concept, introduced in practice during the Meiji period and instituted by law in 1979. Therefore, the posthumous names of the emperors and empresses who reigned prior to 1868 may not be taken as era names by themselves. For example, the year 572—the year in which Emperor Bidatsu assumed the Chrysanthemum Throne – is properly written as "Japanese: 敏達天皇元年" (Bidatsu-Tennō Gannen, "the first year of Emperor Bidatsu"), and not "Japanese: 敏達元年" (Bidatsu Gannen, "the first year of Bidatsu"), although it may be abbreviated as such.[12] By incorporating both proper era names and posthumous imperial names in this manner, it is possible to extend the nengō system to cover all dates from 660 BCE through today.[13]
In addition to the official era name system, in which the era names are selected by the imperial court, one also observes—primarily in the ancient documents and epigraphs of shrines and temples—unofficial era names called, also known as or . Currently, there are over 40 confirmed shinengō, most of them dating from the middle ages. Shinengō used prior to the reestablishment of the era name system in 701 are usually called .
Because official records of shinengō are lacking, the range of dates to which they apply is often unclear. For example, the well-known itsunengō is normally said to refer to 650–654 CE; a poetic synonym for the Hakuchi era. However, alternate interpretations exist. For example, in the Nichūreki, Hakuhō refers to 661–683 CE, and in some medieval temple documents, Hakuhō refers to 672–685 CE. Thus, shinengō may be used as an alternative way of dating periods for which there is no official era name.
Other well-known itsunengō and shinengō include (591–621+ CE), (686), (1460), (1506–1507 or 1507–1509) and (1540–1543).
The most recent shinengō is (1904–1905), named for the Russo-Japanese War.
Edo period scholar Tsurumine Shigenobu proposed that, said to have been used in ancient Kumaso, should also be considered a form of shinengō. This claim is not generally recognized by the academic community. Lists of the proposed Kyūshū nengō can be seen in the Japanese language entries Japanese: [[:ja:鶴峯戊申#襲国偽僣考|鶴峯戊申]] and Japanese: [[:ja:九州王朝説#九州年号表|九州王朝説]].
Certain era names have specific characters assigned to them, for instance ㋿ for the Reiwa period, which can also be written as Japanese: 令和. These are included in Unicode: Code points U+32FF (㋿), U+337B (㍻), U+337C (㍼), U+337D (㍽) and U+337E (㍾) are used for the Reiwa, Heisei, Shōwa, Taishō and Meiji eras, respectively.
Certain calendar libraries support the conversion from and to the era system, as well as rendering of dates using it.
Since the release of Java 8, the Japanese calendar is supported in the new Date and time API for the year Meiji 6 (1873) onwards.[14]
See main article: Japanese calendar era bug. Computers and software manufacturers needed to test their systems in preparation for the new era which began on 1 May 2019. Windows provided a test mechanism to simulate a new era ahead of time.[15] Java Development Kit 11 supported this era using the placeholders "Japanese: 元号" for Japanese, "NewEra" for other languages.[16] The final name was added in JDK 12.0.1, after it was announced by the Japanese government.[17]
Unicode code point U+32FF (㋿) was reserved for representing the new era name, Reiwa.[18]
The list of Japanese era names is the result of a periodization system which was established by Emperor Kōtoku in 645. The system of was irregular until the beginning of the 8th century. After 701, sequential era names developed without interruption across a span of centuries. As of 1 April 2019, there have been 239 era names.
To convert a Japanese year to a Gregorian calendar year, find the first year of the Japanese era name (also called nengō). When found, add the number of the Japanese year, then subtract 1.
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Kōtoku[19] | |||||
| Taika | 645–650 AD | 7 years | Book of Documents, Book of Han, Book of Song | ||
| Hakuchi | 650–654 AD | 5 years | Book of Han | ||
| Emperor Tenmu[20] | |||||
| Shuchō | 686 AD | 3 months | Book of Rites | Also rendered as Suchō, Akamitori, and Akamidori. | |
| Emperor Monmu[21] | |||||
| Taihō | 701–704 AD | 4 years | Classic of Changes | Also rendered as Daihō. | |
| Keiun | 704–708 AD | 5 years | Selections of Refined Literature, Book of Jin | Also rendered as Kyōun. Usage continued by the Empress Genmei upon her ascension to the throne. | |
| Empress Genmei[22] | |||||
| Wadō | 708–715 AD | 8 years | |||
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Empress Genshō[23] | |||||
| Reiki | 715–717 AD | 3 years | Classic of Changes | ||
| Yōrō | 717–724 AD | 8 years | Book of Rites | ||
| Emperor Shōmu[24] | |||||
| Jinki | 724–729 AD | 6 years | Book of Rites with Commentaries of Dai De (大戴禮記), The Literary Expositor | ||
| Tenpyō | 729–749 AD | 21 years | Classic of Changes, Great Learning | Also rendered as Tenbyō and Tenhei. | |
| Tenpyō-kanpō | 749 AD | 4 months | Also rendered as Tenbyō-kanpō and Tenhei-kanpō. | ||
| Empress Kōken[25] | |||||
| Tenpyō-shōhō | 749–757 AD | 9 years | Also rendered as Tenbyō-shōhō and Tenpei-shōhō. | ||
| Tenpyō-hōji | 757–765 AD | 9 years | Also rendered as Tenbyō-hōji and Tenpei-hōji. Usage continued by the Emperor Junnin and the Empress Shōtoku upon their ascension to the throne. | ||
| Empress Shōtoku[26] | |||||
| Tenpyō-jingo | 765–767 AD | 3 years | Also rendered as Tenbyō-jingo and Tenhei-jingo. | ||
| Jingo-keiun | 767–770 AD | 4 years | Usage continued by the Emperor Kōnin upon his ascension to the throne. | ||
| Emperor Kōnin[27] | |||||
| Hōki | 770–781 AD | 12 years | Book of Rites | ||
| Emperor Kanmu[28] | |||||
| Ten'ō | 781–782 AD | 2 years | Classic of Changes | ||
| Enryaku | 782–806 AD | 25 years | Book of Later Han | Usage continued by the Emperor Heizei upon his ascension to the throne. | |
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Heizei[29] | |||||
| Daidō | 806–810 AD | 5 years | Book of Rites | Usage continued by the Emperor Saga upon his ascension to the throne. | |
| Emperor Saga[30] | |||||
| Kōnin | 810–824 AD | 15 years | Usage continued by the Emperor Junna upon his ascension to the throne. | ||
| Emperor Junna[31] | |||||
| Tenchō | 824–834 AD | 11 years | Usage continued by the Emperor Ninmyō upon his ascension to the throne. | ||
| Emperor Ninmyō[32] | |||||
| Jōwa | 834–848 AD | 15 years | Also rendered as Shōwa and Sōwa. | ||
| Kashō | 848–851 AD | 4 years | Also rendered as Kajō. Usage continued by the Emperor Montoku upon his ascension to the throne. | ||
| Emperor Montoku[33] | |||||
| Ninju | 851–854 AD | 4 years | |||
| Saikō | 854–857 AD | 4 years | |||
| Ten'an | 857–859 AD | 3 years | Also rendered as Tennan. Usage continued by the Emperor Seiwa upon his ascension to the throne. | ||
| Emperor Seiwa[34] | |||||
| Jōgan | 859–877 AD | 19 years | Classic of Changes | Usage continued by the Emperor Yōzei upon his ascension to the throne. | |
| Emperor Yōzei[35] | |||||
| Gangyō | 877–885 AD | 9 years | Also rendered as Gankyō and Genkei. Usage continued by the Emperor Kōkō upon his ascension to the throne. | ||
| Emperor Kōkō[36] | |||||
| Ninna | 885–889 AD | 5 years | Also rendered as Ninwa. Usage continued by the Emperor Uda upon his ascension to the throne. | ||
| Emperor Uda[37] | |||||
| Kanpyō | 889–898 AD | 10 years | Also rendered as Kanpei, Kanbyō, Kanbei, and Kanhei. Usage continued by the Emperor Daigo upon his ascension to the throne. | ||
| Emperor Daigo[38] | |||||
| Shōtai | 898–901 AD | 4 years | |||
| Engi | 901–923 AD | 23 years | Book of Documents | ||
| Enchō | 923–931 AD | 9 years | Selections of Refined Literature | Usage continued by the Emperor Suzaku upon his ascension to the throne. | |
| Emperor Suzaku[39] | |||||
| Jōhei | 931–938 AD | 8 years | Book of Han | Also rendered as Shōhei. | |
| Tengyō | 938–947 AD | 10 years | Book of Han | Also rendered as Tenkei and Tenkyō. Usage continued by the Emperor Murakami upon his ascension to the throne. | |
| Emperor Murakami[40] | |||||
| Tenryaku | 947–957 AD | 11 years | Analects | Also rendered as Tenreki. | |
| Tentoku | 957–961 AD | 5 years | Classic of Changes | ||
| Ōwa | 961–964 AD | 4 years | Book of Jin | ||
| Kōhō | 964–968 AD | 5 years | Book of Documents | Usage continued by the Emperor Reizei upon his ascension to the throne. | |
| Emperor Reizei[41] | |||||
| Anna | 968–970 AD | 3 years | Book of Rites | Also rendered as Anwa. Usage continued by the Emperor En'yū upon his ascension to the throne. | |
| Emperor En'yū[42] | |||||
| Tenroku | 970–974 AD | 5 years | |||
| Ten'en | 974–976 AD | 3 years | |||
| Jōgen | 976–978 AD | 3 years | Also rendered as Teigen. | ||
| Tengen | 978–983 AD | 6 years | |||
| Eikan | 983–985 AD | 3 years | Book of Documents | Also rendered as Yōkan. Usage continued by the Emperor Kazan upon his ascension to the throne. | |
| Emperor Kazan[43] | |||||
| Kanna | 985–987 AD | 3 years | Also rendered as Kanwa. Usage continued by the Emperor Ichijō upon his ascension to the throne. | ||
| Emperor Ichijō[44] | |||||
| Eien | 987–989 AD | 3 years | Book of Han, Book of Later Han | Also rendered as Yōen. | |
| Eiso | 989–990 AD | 2 years | Book of Jin, Old Book of Tang | Also rendered as Yōso. | |
| Shōryaku | 990–995 AD | 6 years | Also rendered as Jōryaku and Shōreki. | ||
| Chōtoku | 995–999 AD | 5 years | Admonishment by the Colonel of the City Gates (城門校尉箴) | Also rendered as Jōryaku and Shōreki. | |
| Chōhō | 999–1004 AD | 6 years | Discourses of the States | ||
| Kankō | 1004–1012 AD | 9 years | Book of Han | Usage continued by the Emperor Sanjō upon his ascension to the throne. | |
| Emperor Sanjō[45] | |||||
| Chōwa | 1012–1017 AD | 6 years | Book of Rites | Usage continued by the Emperor Go-Ichijō upon his ascension to the throne. | |
| Emperor Go-Ichijō[46] | |||||
| Kannin | 1017–1021 AD | 5 years | Records of Kuaiji (會稽記) | ||
| Jian | 1021–1024 AD | 4 years | Book of Han | Also rendered as Chian. | |
| Manju | 1024–1028 AD | 5 years | Classic of Poetry | ||
| Chōgen | 1028–1037 AD | 10 years | Six Secret Teachings | Usage continued by the Emperor Go-Suzaku upon his ascension to the throne. | |
| Emperor Go-Suzaku[47] | |||||
| Chōryaku | 1037–1040 AD | 4 years | Spring and Autumn Annals, Book of Jin | Also rendered as Chōreki. | |
| Chōkyū | 1040–1044 AD | 5 years | Book of the Way and of Virtue | ||
| Kantoku | 1044–1046 AD | 3 years | Book of Later Han | Usage continued by the Emperor Go-Reizei upon his ascension to the throne. | |
| Emperor Go-Reizei[48] | |||||
| Eishō | 1046–1053 AD | 8 years | Book of Documents, Book of Jin, Book of Song | Also rendered as Eijō and Yōjō. | |
| Tengi | 1053–1058 AD | 6 years | Book of the Master Who Embraces Simplicity | Also rendered as Tenki. | |
| Kōhei | 1058–1065 AD | 8 years | Book of Later Han | ||
| Jiryaku | 1065–1069 AD | 5 years | Correct Interpretation of the Book of Documents (尚書正義) | Also rendered as Chiryaku. Usage continued by the Emperor Go-Sanjō upon his ascension to the throne. | |
| Emperor Go-Sanjō[49] | |||||
| Enkyū | 1069–1074 AD | 6 years | Book of Documents | Usage continued by the Emperor Shirakawa upon his ascension to the throne. | |
| Emperor Shirakawa[50] | |||||
| Jōhō | 1074–1077 AD | 4 years | Book of Documents | Also rendered as Shōhō and Shōho. | |
| Jōryaku | 1077–1081 AD | 5 years | Weicheng Dianxun (維城典訓) | Also rendered as Shōryaku and Shōreki. | |
| Eihō | 1081–1084 AD | 4 years | Book of Documents | Also rendered as Yōhō. | |
| Ōtoku | 1084–1087 AD | 4 years | Comprehensive Meaning of White Tiger Pavilion | Usage continued by the Emperor Horikawa upon his ascension to the throne. | |
| Emperor Horikawa[51] | |||||
| Kanji | 1087–1094 AD | 8 years | Book of Rites | ||
| Kahō | 1094–1096 AD | 3 years | Records of the Grand Historian | ||
| Eichō | 1096–1097 AD | 2 years | Book of Later Han | Also rendered as Yōchō. | |
| Jōtoku | 1097–1099 AD | 3 years | Classic of Changes | Also rendered as Shōtoku. | |
| Kōwa | 1099–1104 CE | 6 years | Theories of Politics (政論) | ||
| Chōji | 1104–1106 CE | 3 years | Book of Han | ||
| Kajō | 1106–1108 CE | 3 years | Book of Han | Usage continued by the Emperor Toba upon his ascension to the throne. | |
| Emperor Toba[52] | |||||
| Tennin | 1108–1110 AD | 3 years | Selections of Refined Literature | ||
| Ten'ei | 1110–1113 AD | 4 years | Book of Documents | Also rendered as Ten'yō. | |
| Eikyū | 1113–1118 AD | 6 years | Mao Commentary | Also rendered as Yōkyū. | |
| Gen'ei | 1118–1120 AD | 3 years | Also rendered as Gen'yō. | ||
| Hōan | 1120–1124 AD | 5 years | Usage continued by the Emperor Sutoku upon his ascension to the throne. | ||
| Emperor Sutoku[53] | |||||
| Tenji | 1124–1126 AD | 3 years | Classic of Changes | Also rendered as Tenchi. | |
| Daiji | 1126–1131 AD | 6 years | Hetu Tingzuofu (河圖挺佐輔) | Also rendered as Taiji. | |
| Tenshō | 1131–1132 AD | 2 years | Book of Han | Also rendered as Tenjō. | |
| Chōshō | 1132–1135 AD | 4 years | Records of the Grand Historian | Also rendered as Chōjō. | |
| Hōen | 1135–1141 AD | 7 years | Selections of Refined Literature | ||
| Eiji | 1141–1142 AD | 2 years | On the Standards for Literature (典論), Book of Jin | Usage continued by the Emperor Konoe upon his ascension to the throne. | |
| Emperor Konoe[54] | |||||
| Kōji | 1142–1144 AD | 3 years | Book of Song | ||
| Ten'yō | 1144–1145 AD | 2 years | Book of Later Han | Also rendered as Tennyō. | |
| Kyūan | 1145–1151 AD | 7 years | Book of Jin | ||
| Ninpei | 1151–1154 AD | 4 years | Book of Later Han | Also rendered as Ninpyō, Ninbyō, Ninhyō, and Ninhei. | |
| Kyūju | 1154–1156 AD | 3 years | Book of the Master Who Embraces Simplicity | Usage continued by the Emperor Go-Shirakawa upon his ascension to the throne. | |
| Emperor Go-Shirakawa[55] | |||||
| Hōgen | 1156–1159 AD | 4 years | Instructions for the Yan Clan (顏氏家訓) | Also rendered as Hogen. Usage continued by the Emperor Nijō upon his ascension to the throne. | |
| Emperor Nijō[56] | |||||
| Heiji | 1159–1160 AD | 2 years | Records of the Grand Historian | Also rendered as Byōji. | |
| Eiryaku | 1160–1161 AD | 2 years | Book of Later Han | Also rendered as Yōryaku. | |
| Ōhō | 1161–1163 AD | 3 years | Book of Documents | Also rendered as Ōpō. | |
| Chōkan | 1163–1165 AD | 3 years | Weicheng Dianxun (維城典訓) | Also rendered as Chōgan. | |
| Eiman | 1165–1166 AD | 2 years | Book of Han | Also rendered as Yōman. Usage continued by the Emperor Rokujō upon his ascension to the throne. | |
| Emperor Rokujō[57] | |||||
| Nin'an | 1166–1169 AD | 4 years | Correct Interpretation of the Mao Commentary (毛詩正義) | Also rendered as Ninnan. Usage continued by the Emperor Takakura upon his ascension to the throne. | |
| Emperor Takakura | |||||
| Kaō | 1169–1171 AD | 3 years | Book of Han | ||
| Jōan | 1171–1175 AD | 5 years | Book of Documents | Also rendered as Shōan. | |
| Angen | 1175–1177 AD | 3 years | Book of Han | ||
| Jishō | 1177–1181 AD | 5 years | Hetu Tingzuofu (河圖挺作輔) | Also rendered as Jijō and Chishō. Usage continued by the Emperor Antoku upon his ascension to the throne. | |
| Emperor Antoku[58] | |||||
| Yōwa | 1181–1182 AD | 8 years | Book of Later Han | ||
| Juei | 1182–1185 AD | 4 years | Classic of Poetry | Also used by the Emperor Go-Toba from 1183 AD to 1184 AD. | |
| Emperor Go-Toba[59] | |||||
| Juei | 1183–1184 AD | 2 years | Classic of Poetry | Also used by the Emperor Antoku from 1182 AD to 1185 AD. | |
| Genryaku | 1184–1185 AD | 2 years | Shangshu Kaolingyao (尚書考靈耀) | ||
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Go-Toba | |||||
| Bunji | 1185–1190 CE | 6 years | Book of Rites | Also rendered as Monchi. | |
| Kenkyū | 1190–1199 CE | 10 years | Book of Jin | Usage continued by the Emperor Tsuchimikado upon his ascension to the throne. | |
| Emperor Tsuchimikado[60] | |||||
| Shōji | 1199–1201 CE | 3 years | Zhuangzi | Also rendered as Shōchi. | |
| Kennin | 1201–1204 CE | 4 years | Selections of Refined Literature | ||
| Genkyū | 1204–1206 CE | 3 years | Correct Interpretation of the Mao Commentary (毛詩正義) | ||
| Ken'ei | 1206–1207 CE | 2 years | Selections of Refined Literature | Also rendered as Ken'yō. | |
| Jōgen | 1207–1211 CE | 5 years | Comprehensive Institutions | Also rendered as Shōgen. Usage continued by the Emperor Juntoku upon his ascension to the throne. | |
| Emperor Juntoku[61] | |||||
| Kenryaku | 1211–1213 CE | 3 years | Book of Later Han | Also rendered as Kenreki. | |
| Kempo | 1213–1219 CE | 7 years | Book of Documents | Also rendered as Kenhō. | |
| Jōkyū | 1219–1222 CE | 4 years | Apocrypha of the Classic of Poetry (詩緯) | Also rendered as Shōkyū. Usage continued by the Emperor Chūkyō and the Emperor Go-Horikawa upon their ascension to the throne. | |
| Emperor Go-Horikawa[62] | |||||
| Jōō | 1222–1224 CE | 3 years | Classic of Changes | Also rendered as Teiō. | |
| Gennin | 1224–1225 CE | 2 years | Classic of Changes | ||
| Karoku | 1225–1227 CE | 3 years | Records of Diverse Matters | ||
| Antei | 1227–1229 CE | 3 years | Classic of Changes | Also rendered as Anjō. | |
| Kangi | 1229–1232 CE | 4 years | Book of Wei | Also rendered as Kanki. | |
| Jōei | 1232–1233 CE | 2 years | Classic of Changes | Also rendered as Teiei. Usage continued by the Emperor Shijō upon his ascension to the throne. | |
| Emperor Shijō[63] | |||||
| Tenpuku | 1233–1234 CE | 2 years | Book of Documents | Also rendered as Tenfuku. | |
| Bunryaku | 1234–1235 CE | 2 years | Selections of Refined Literature | Also rendered as Monryaku and Monreki. | |
| Katei | 1235–1238 CE | 4 years | Book of Northern Qi | ||
| Ryakunin | 1238–1239 CE | 2 years | Book of Sui | Also rendered as Rekinin. | |
| En'ō | 1239–1240 CE | 2 years | Selections of Refined Literature | Also rendered as Ennō. | |
| Ninji | 1240–1243 CE | 4 years | New Book of Tang | Also rendered as Ninchi. Usage continued by the Emperor Go-Saga upon his ascension to the throne. | |
| Emperor Go-Saga[64] | |||||
| Kangen | 1243–1247 CE | 5 years | Book of Song | Usage continued by the Emperor Go-Fukakusa upon his ascension to the throne. | |
| Emperor Go-Fukakusa[65] | |||||
| Hōji | 1247–1249 CE | 3 years | Luxuriant Dew of the Spring and Autumn Annals | ||
| Kenchō | 1249–1256 CE | 8 years | Book of Later Han | ||
| Kōgen | 1256–1257 CE | 2 years | |||
| Shōka | 1257–1259 CE | 3 years | Classified Collection Based on the Classics and Other Literature | ||
| Shōgen | 1259–1260 CE | 2 years | Apocrypha of the Classic of Poetry (詩緯) | Usage continued by the Emperor Kameyama upon his ascension to the throne. | |
| Emperor Kameyama[66] | |||||
| Bun'ō | 1260–1261 CE | 2 years | Book of Jin | Also rendered as Bunnō. | |
| Kōchō | 1261–1264 CE | 4 years | The Political Program of the Zhenguan Period (貞觀政要) | ||
| Bun'ei | 1264–1275 CE | 12 years | Book of Later Han | Usage continued by the Emperor Go-Uda upon his ascension to the throne. | |
| Emperor Go-Uda[67] | |||||
| Kenji | 1275–1278 CE | 4 years | Rites of Zhou | ||
| Kōan | 1278–1288 CE | 11 years | Veritable Records of the Emperor Taizong of Tang (唐太宗實錄) | Usage continued by the Emperor Fushimi upon his ascension to the throne. | |
| Emperor Fushimi[68] | |||||
| Shōō | 1288–1293 CE | 6 years | Notes on the Mao Commentary (毛詩注) | ||
| Einin | 1293–1299 CE | 7 years | Book of Jin | Usage continued by the Emperor Go-Fushimi upon his ascension to the throne. | |
| Emperor Go-Fushimi[69] | |||||
| Shōan | 1299–1302 CE | 4 years | The School Sayings of Confucius | Usage continued by the Emperor Go-Nijō upon his ascension to the throne. | |
| Emperor Go-Nijō[70] | |||||
| Kengen | 1302–1303 CE | 2 years | Classic of Changes | ||
| Kagen | 1303–1306 CE | 4 years | Classified Collection Based on the Classics and Other Literature | ||
| Tokuji | 1306–1308 CE | 3 years | The Commentary of Zuo | Usage continued by the Emperor Hanazono upon his ascension to the throne. | |
| Emperor Hanazono[71] | |||||
| Enkyō | 1308–1311 CE | 4 years | Book of Later Han | Also rendered as Engyō and Enkei. | |
| Ōchō | 1311–1312 CE | 2 years | Old Book of Tang | ||
| Shōwa | 1312–1317 CE | 6 years | Old Book of Tang | ||
| Bunpō | 1317–1319 CE | 3 years | Book of Liang | Also rendered as Bunhō. Usage continued by the Emperor Go-Daigo upon his ascension to the throne. | |
| Emperor Go-Daigo[72] | |||||
| Gen'ō | 1319–1321 CE | 3 years | Old Book of Tang | Also rendered as Gennō. | |
| Genkō | 1321–1324 CE | 4 years | Classic of Changes | ||
| Shōchū | 1324–1326 CE | 3 years | Classic of Changes | ||
| Karyaku | 1326–1329 CE | 4 years | Old Book of Tang | ||
| Gentoku | 1329–1332 CE | 4 years | Classic of Changes, Correct Interpretation of the Classic of Changes (周易正義) | ||
| Genkō | 1331–1334 CE | 4 years | Classified Collection Based on the Classics and Other Literature | ||
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Go-Daigo | |||||
| Kenmu | 1334–1336 CE | 3 years | Book of Later Han | Also rendered as Kenbu. Also used by the Emperor Kōmyō from 1336 CE to 1338 CE. | |
| Engen | 1336–1340 CE | 5 years | Book of Liang | Usage continued by the Emperor Go-Murakami upon his ascension to the throne. | |
| Emperor Go-Murakami | |||||
| Kōkoku | 1340–1347 CE | 8 years | The Commentary of Zuo, Selections of Refined Literature, New History of the Five Dynasties | ||
| Shōhei | 1347–1370 CE | 24 years | Book of Song | Usage continued by the Emperor Chōkei upon his ascension to the throne. | |
| Emperor Chōkei | |||||
| Kentoku | 1370–1372 CE | 3 years | Selections of Refined Literature | ||
| Bunchū | 1372–1375 CE | 4 years | Classic of Changes | ||
| Tenju | 1375–1381 CE | 7 years | Records of the Grand Historian | ||
| Kōwa | 1381–1384 CE | 4 years | Book of Documents | Usage continued by the Emperor Go-Kameyama upon his ascension to the throne. | |
| Emperor Go-Kameyama | |||||
| Genchū | 1384–1392 CE | 9 years | Classic of Changes | Genchū 9 was superseded by Meitoku 3 in 1392 CE. | |
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Kōgon | |||||
| Shōkyō | 1332–1333 CE | 2 years | Correct Interpretation of the Classic of Changes (周易正義) | Also rendered as Shōkyō. | |
| Emperor Kōmyō | |||||
| Kenmu | 1336–1338 CE | 3 years | Book of Later Han | Also rendered as Kenbu. Also used by the Emperor Go-Daigo from 1334 CE to 1336 CE. | |
| Ryakuō | 1338–1342 CE | 5 years | Records of Emperors and Kings (帝王世紀) | Also rendered as Rekiō. | |
| Kōei | 1342–1345 CE | 4 years | Book of Han | ||
| Jōwa | 1345–1350 CE | 6 years | Classified Collection Based on the Classics and Other Literature | Also rendered as Teiwa. Usage continued by the Emperor Sukō upon his ascension to the throne. | |
| Emperor Sukō | |||||
| Kannō | 1350–1352 CE | 3 years | Zhuangzi | Also rendered as Kan'ō. Usage continued by the Emperor Go-Kōgon upon his ascension to the throne. | |
| Emperor Go-Kōgon | |||||
| Bunna | 1352–1356 CE | 5 years | Records of the Three Kingdoms, Old Book of Tang | Also rendered as Bunwa. | |
| Enbun | 1356–1361 CE | 6 years | Book of Han | ||
| Kōan | 1361–1362 CE | 2 years | Correct Interpretation of the Records of the Grand Historian (史記正義), Old Book of Tang | ||
| Jōji | 1362–1368 CE | 7 years | Classic of Changes | Also rendered as Teiji. | |
| Ōan | 1368–1375 CE | 8 years | Correct Interpretation of the Mao Commentary (毛詩正義) | Usage continued by the Emperor Go-En'yū upon his ascension to the throne. | |
| Emperor Go-En'yū | |||||
| Eiwa | 1375–1379 CE | 5 years | Book of Documents, Classified Collection Based on the Classics and Other Literature | ||
| Kōryaku | 1379–1381 CE | 3 years | Old Book of Tang | ||
| Eitoku | 1381–1384 CE | 4 years | The Governing Principles of Ancient China (羣書治要) | Usage continued by the Emperor Go-Komatsu upon his ascension to the throne. | |
| Emperor Go-Komatsu | |||||
| Shitoku | 1384–1387 CE | 4 years | Classic of Filial Piety | Also rendered as Meitoku | |
| Kakei | 1387–1389 CE | 3 years | Correct Interpretation of the Mao Commentary (毛詩正義) | Also rendered as Kakyō. | |
| Kōō | 1389–1390 CE | 2 years | Selections of Refined Literature | ||
| Meitoku | 1390–1394 CE | 5 years | Book of Rites | Meitoku 3 superseded Genchū 9 in 1392 CE. | |
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Go-Komatsu | |||||
| Ōei | 1394–1428 CE | 35 years | Institutional History of Tang | Usage continued by the Emperor Shōkō upon his ascension to the throne. | |
| Emperor Shōkō[73] | |||||
| Shōchō | 1428–1429 CE | 2 years | Correct Interpretation of the Book of Rites (禮記正義) | Usage continued by the Emperor Go-Hanazono upon his ascension to the throne. | |
| Emperor Go-Hanazono[74] | |||||
| Eikyō | 1429–1441 CE | 13 years | Book of Later Han | Also rendered as Eikō. | |
| Kakitsu | 1441–1444 CE | 4 years | Classic of Changes | Also rendered as Kakichi. | |
| Bun'an | 1444–1449 CE | 6 years | Book of Documents, Book of Jin | Also rendered as Bunnan. | |
| Hōtoku | 1449–1452 CE | 4 years | Old Book of Tang | ||
| Kyōtoku | 1452–1455 CE | 4 years | Book of Documents | ||
| Kōshō | 1455–1457 CE | 3 years | Book of Documents, Records of the Grand Historian | ||
| Chōroku | 1457–1460 CE | 4 years | Han Feizi | ||
| Kanshō | 1460–1466 CE | 7 years | The School Sayings of Confucius | Usage continued by the Emperor Go-Tsuchimikado upon his ascension to the throne. | |
| Emperor Go-Tsuchimikado[75] | |||||
| Bunshō | 1466–1467 CE | 2 years | Xunzi | Also rendered as Monshō. | |
| Ōnin | 1467–1469 CE | 3 years | Weicheng Dianxun (維城典訓) | ||
| Bunmei | 1469–1487 CE | 19 years | Classic of Changes | ||
| Chōkyō | 1487–1489 CE | 3 years | Selections of Refined Literature, The Commentary of Zuo, Book of Later Han | ||
| Entoku | 1489–1492 CE | 4 years | Mencius | ||
| Meiō | 1492–1501 CE | 10 years | Classic of Changes | Usage continued by the Emperor Go-Kashiwabara upon his ascension to the throne. | |
| Emperor Go-Kashiwabara[76] | |||||
| Bunki | 1501–1504 CE | 4 years | The Literary Expositor | ||
| Eishō | 1504–1521 CE | 18 years | Apocrypha of the Classic of Changes (周易緯) | ||
| Daiei | 1521–1528 CE | 8 years | Comprehensive Institutions | Usage continued by the Emperor Go-Nara upon his ascension to the throne. | |
| Emperor Go-Nara[77] | |||||
| Kyōroku | 1528–1532 CE | 5 years | Classic of Changes | ||
| Tenbun | 1532–1555 CE | 24 years | Classic of Changes | Also rendered as Tenmon. | |
| Kōji | 1555–1558 CE | 4 years | Book of Northern Qi | Usage continued by the Emperor Ōgimachi upon his ascension to the throne. | |
| Emperor Ōgimachi[78] | |||||
| Eiroku | 1558–1570 CE | 13 years | The Governing Principles of Ancient China (羣書治要) | Also rendered as Yōroku. | |
| Genki | 1570–1573 CE | 4 years | Mao Commentary, Selections of Refined Literature | ||
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Ōgimachi | |||||
| Tenshō | 1573–1592 CE | 20 years | Selections of Refined Literature, Book of the Way and of Virtue | Usage continued by the Emperor Go-Yōzei upon his ascension to the throne. | |
| Emperor Go-Yōzei[79] | |||||
| Bunroku | 1592–1596 CE | 5 years | Comprehensive Institutions | ||
| Keichō | 1596–1615 CE | 20 years | Correct Interpretation of the Mao Commentary (毛詩注疏) | Also rendered as Kyōchō. Usage continued by the Emperor Go-Mizunoo upon his ascension to the throne. | |
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Go-Mizunoo[80] | |||||
| Genna | 1615–1624 CE | 10 years | Era name of the Emperor Xianzong of Tang | Also rendered as Genwa. | |
| Kan'ei | 1624–1644 CE | 21 years | Collected Commentaries on the Classic of Poetry (詩集傳) | Usage continued by the Empress Meishō and the Emperor Go-Kōmyō upon their ascension to the throne. | |
| Emperor Go-Kōmyō[81] | |||||
| Shōhō | 1645–1648 CE | 4 years | Book of Documents | ||
| Keian | 1648–1652 CE | 5 years | Classic of Changes | Also rendered as Kyōan. | |
| Jōō | 1652–1655 CE | 4 years | Book of Jin | Also rendered as Shōō. Usage continued by the Emperor Go-Sai upon his ascension to the throne. | |
| Emperor Go-Sai[82] | |||||
| Meireki | 1655–1658 CE | 4 years | Book of Han, Book of Later Han | Also rendered as Myōryaku and Meiryaku. | |
| Manji | 1658–1661 CE | 4 years | Records of the Grand Historian, The Political Program of the Zhenguan Period (貞觀政要) | Also rendered as Manchi. | |
| Kanbun | 1661–1673 CE | 13 years | Xunzi | Usage continued by the Emperor Reigen upon his ascension to the throne. | |
| Emperor Reigen[83] | |||||
| Enpō | 1673–1681 CE | 9 years | Book of Sui | Also rendered as Enhō. Formerly written as "" in kanji. | |
| Tenna | 1681–1684 CE | 4 years | Book of Documents, Book of Han, Book of Later Han, Zhuangzi | Also rendered as Tenwa. | |
| Jōkyō | 1684–1688 CE | 5 years | Classic of Changes | Usage continued by the Emperor Higashiyama upon his ascension to the throne. | |
| Emperor Higashiyama[84] | |||||
| Genroku | 1688–1704 CE | 16 years | Selections of Refined Literature | ||
| Hōei | 1704–1711 CE | 8 years | Old Book of Tang | Usage continued by the Emperor Nakamikado upon his ascension to the throne. | |
| Emperor Nakamikado[85] | |||||
| Shōtoku | 1711–1716 CE | 6 years | Book of Documents | ||
| Kyōhō | 1716–1736 CE | 21 years | Book of Zhou | Usage continued by the Emperor Sakuramachi upon his ascension to the throne. | |
| Emperor Sakuramachi[86] | |||||
| Genbun | 1736–1741 CE | 6 years | Selections of Refined Literature | ||
| Kanpō | 1741–1744 CE | 4 years | Discourses of the States | Also rendered as Kanhō. | |
| Enkyō | 1744–1748 CE | 5 years | Classified Collection Based on the Classics and Other Literature | Usage continued by the Emperor Momozono upon his ascension to the throne. | |
| Emperor Momozono[87] | |||||
| Kan'en | 1748–1751 CE | 4 years | Selections of Refined Literature | ||
| Hōreki | 1751–1764 CE | 14 years | The Political Program of the Zhenguan Period (貞觀政要) | Also rendered as Hōryaku. Usage continued by the Empress Go-Sakuramachi upon her ascension to the throne. | |
| Empress Go-Sakuramachi[88] | |||||
| Meiwa | 1764–1772 CE | 9 years | Book of Documents | Also rendered as Myōwa. Usage continued by the Emperor Go-Momozono upon his ascension to the throne. | |
| Emperor Go-Momozono[89] | |||||
| An'ei | 1772–1781 CE | 10 years | Selections of Refined Literature | Usage continued by the Emperor Kōkaku upon his ascension to the throne. | |
| Emperor Kōkaku[90] | |||||
| Tenmei | 1781–1789 CE | 9 years | Book of Documents | ||
| Kansei | 1789–1801 CE | 13 years | The Commentary of Zuo | ||
| Kyōwa | 1801–1804 CE | 4 years | Selections of Refined Literature | ||
| Bunka | 1804–1818 CE | 15 years | Classic of Changes, Book of Later Han | Usage continued by the Emperor Ninkō upon his ascension to the throne. | |
| Emperor Ninkō[91] | |||||
| Bunsei | 1818–1830 CE | 13 years | Book of Documents | ||
| Tenpō | 1830–1844 CE | 15 years | Book of Documents | Also rendered as Tenhō. | |
| Kōka | 1844–1848 CE | 5 years | Book of Documents | Usage continued by the Emperor Kōmei upon his ascension to the throne. | |
| Emperor Kōmei | |||||
| Kaei | 1848–1854 CE | 7 years | Book of Song | ||
| Ansei | 1854–1860 CE | 7 years | The Governing Principles of Ancient China (羣書治要) | ||
| Man'en | 1860–1861 CE | 2 years | Book of Later Han | ||
| Bunkyū | 1861–1864 CE | 4 years | Book of Later Han | ||
| Genji | 1864–1865 CE | 2 years | Classic of Changes, Records of the Three Kingdoms | ||
| Keiō | 1865–1868 CE | 4 years | Selections of Refined Literature | Usage continued by the Emperor Meiji upon his ascension to the throne. | |
The "one reign, one era name" system was implemented in 1868 AD.
| Era name | Period of use | Length of use | Derived from | Remark | |
|---|---|---|---|---|---|
| Emperor Meiji | |||||
| Meiji | 1868–1912 AD | 45 years | Classic of Changes | In 1873 Japan adopted the Seireki (西暦), the Common Era. Nowadays, Japanese people know it as well as the regnal eras. Prior to the introduction of the Gregorian calendar in 1873, the reference calendar was based on the lunisolar Chinese calendar. | |
| Emperor Taishō | |||||
| Taishō | 1912–1926 AD | 15 years | Classic of Changes | Rejected proposals were Tenkō, Kōka, Eian, Kentoku, Shōtoku . | |
| Emperor Shōwa | |||||
| Shōwa | 1926–1989 AD | 64 years | Book of Documents | Rejected proposals were Jinka, Genka, Jinwa, Dōwa, Keimei, Junmei, Meiho, Kan'an, Gen'an, Ryūsei, Teigyō, Kōbun, Shōmei, Kyōchū . | |
| Akihito | |||||
| Heisei | 1989–2019 AD | 31 years | Records of the Grand Historian, Book of Documents | Rejected proposals were Shūbun, Seika . | |
| Naruhito | |||||
| Reiwa | 2019 AD–present | Man'yōshū | First Japanese era name extracted from Japanese literature instead of Chinese literature.[92] [93] [94] [95] Rejected proposals were Eikō, Kyūka, Kōshi (also rendered as Kōji;), Banna (also rendered as Banwa;), Banpo (also rendered as Banhō;). | ||
Unofficial non- periods before 701 are called . Pre-Taika chronology intervals include:
Post-Taika chronology intervals not covered by the system include: