Japanese History Digest

The Heian period

The Heian period

The Heian period refers to the approximately 400 years from 794, when Emperor Kanmu moved the capital to Heian-kyō (present-day Kyoto), until the establishment of the Kamakura shogunate in 1185. During this era, while inheriting the ritsuryō system of the Nara period, politics centered around the aristocracy, and a uniquely Japanese culture flourished and developed significantly.

 

The era of Emperor Kanmu

Emperor Kanmu ascended the throne upon the abdication of Emperor Kōnin. In 784 (Enryaku 3), he transferred the capital to Nagaoka-kyō. However, due to problems such as the assassination of Fujiwara no Tanetsugu, the official in charge of constructing the Nagaoka Palace, as well as the site’s unfavorable geographical conditions, the capital was moved again in 794 (Enryaku 13) to Heian-kyō. Heian-kyō was chosen for its convenient transportation links to Naniwa and the western provinces via river transport along the Yodo River system, and because it allowed the court to avoid the influence of the powerful Buddhist institutions of Nara.

Emperor Kanmu also worked to restore and strengthen the ritsuryō state system. In 792 (Enryaku 11), he reformed the military organization by abolishing the conscription-based gundan system in all provinces except Mutsu, Dewa, Sado, and the provinces of the Saikaidō. In its place, he adopted the kondei system, recruiting soldiers from among the sons of local district officials and influential local farmers. This reform reduced the burden on the populace and helped maintain public order in the provinces. In addition, to prevent corruption during the transfer of office by provincial governors, he established the kageyushi (inspectors responsible for overseeing official handovers). Furthermore, in the northeastern regions, he advanced control over the Emishi by dispatching Sakanoue no Tamuramaro, whom he appointed as Seii Taishōgun.

 

The Era of Emperors Heizei and Saga

During the reigns of Emperor Heizei, who succeeded Emperor Kanmu, and subsequently Emperor Saga, the political policies established under Emperor Kanmu were largely carried on. In 809, Emperor Heizei abdicated the throne due to illness in favor of his half-brother, Emperor Saga, becoming the retired Emperor Heizei, and moved to Heijō-kyō. However, Fujiwara no Kusuko and her brother Fujiwara no Nakanari plotted to restore the retired emperor to the throne and to return the capital to Heijō-kyō, and in 810 they instigated the Kusuko Incident. This rebellion was suppressed by Emperor Saga, and thereafter the authority of the emperor was strengthened.

To ensure the smooth conduct of government affairs, Emperor Saga established the Kurōdodokoro immediately after his accession as an extra-legal office (ryōgekan) to handle imperial edicts and confidential state matters on behalf of the emperor, appointing Fujiwara no Fuyutsugu and Kose no Notari as kurōdo no tō. In addition, the office of kebiishi (police and judicial officials) was later established to maintain public order in the capital and to oversee judicial matters. Furthermore, Emperor Saga promoted the consolidation of ritsuryō governance by organizing the kyaku (supplementary and corrective statutes to the ritsuryō codes) and the shiki (detailed regulations for their enforcement), and by overseeing the compilation of the Kōnin Code (Kōnin kyakushiki).

 

The Rise of The Fujiwara Northern House (Hokke)

After the decline of the Fujiwara Shikike following the Kusuko Incident, the Fujiwara Hokke (Northern Branch of the Fujiwara clan) gradually rose to prominence. Fujiwara no Yoshifusa, the son of Fujiwara no Fuyutsugu, eliminated figures such as Tomo no Kowamine and Tachibana no Hayanari in the Jōwa Incident of 842, and secured the appointment of Prince Michiyasu—son of Yoshifusa’s sister Junshi—as crown prince (he later became Emperor Montoku). Furthermore, after Tomo no Yoshio was disgraced in the Ōtenmon Incident of 866, Yoshifusa became the first non-imperial noble to assume the office of regent (sesshō), greatly enhancing the status of the Fujiwara Hokke.

Yoshifusa’s adopted son, Fujiwara no Mototsune, became formally appointed kanpaku (chief adviser to the emperor) in 889 (Kanpyō 1), following the Ahe Incident of 887 (Ninna 3), thereby solidifying the foundations of regency politics (sekkan seiji). After Mototsune’s death, Emperor Uda attempted to curb the power of the Fujiwara clan by ruling without a kanpaku and by promoting Sugawara no Michizane. However, during the reign of Emperor Daigo, Michizane was demoted and exiled to the post of Acting Governor-General of Dazaifu as a result of slander by Fujiwara no Tokihira (the Shōtai Incident of 901), and the political dominance of the Fujiwara Hokke was thus maintained.

Moreover, in the Anna Incident of 969 (Anna 2), Fujiwara no Saneyori brought about the downfall of Minamoto no Takaakira, enabling the Fujiwara Hokke to establish a position of overwhelming superiority over other clans within the imperial court.

 

Regency Government (Sekkan Seiji)

In the mid-Heian period, a political system developed in which regents (sesshō) and chief advisers (kanpaku), centered on the Fujiwara Hokke (Northern Branch of the Fujiwara clan), assisted the emperor and assumed responsibility for government affairs. Especially after the Anna Incident of 969, rival clans were excluded from political power, and the offices of regent and chief adviser came to be monopolized by the Fujiwara Hokke. The height of regency government was reached during the time of Fujiwara no Michinaga and his son Yorimichi. Michinaga married his daughters one after another to emperors and wielded enormous power as the maternal relative of the imperial family. Yorimichi likewise exercised authority over the government for an extended period, bringing the power of the Fujiwara clan to its peak.

During this time, the regent and chief adviser exerted great influence over appointments and state policy and played a central role in political administration. Nevertheless, the emperor continued to retain an important position as the ultimate source of authority. While power struggles within the Fujiwara clan itself became the main axis of politics, warfare broke out in the provinces, including the Former Nine Years’ War (1051–1062) and the Later Three Years’ War (1083–1087), and the court’s control and prestige gradually began to weaken. Eventually, Emperor Go-Sanjō ascended the throne and ruled directly without appointing a regent or chief adviser, and with the subsequent establishment of cloistered rule (insei) by the retired Emperor Shirakawa, regency government gradually declined.

 

The Growth of Warrior Bands

While aristocratic culture flourished in Heian-kyō, the system of governance based on the ritsuryō codes gradually weakened in the provinces. Many provincial governors (kokushi) became absentee officials (yōnin), failing to take up residence in their assigned provinces, and actual administration and tax collection came to be entrusted to locally based zuryō (provincial administrators) and local officials. As a result, governance by the provincial government offices (kokuga) deteriorated, and the burden on the local population grew increasingly heavy.

Amid these conditions, local magnates developed landed estates (shōen) in cooperation with temples, shrines, and aristocrats. By donating these estates, they obtained privileges of tax exemption (fuyu) and immunity from official entry (funyū), thereby avoiding taxation and interference by the provincial government. As the foundations of the ritsuryō system eroded, these local elites organized armed retainers, strengthened their effective control over their regions through the use of force, and gradually developed into organized warrior bands (bushidan).

In the tenth century, Taira no Masakado launched a rebellion against the provincial government in the eastern provinces (the Rebellion of Taira no Masakado), while in western Japan Fujiwara no Sumitomo led pirate forces, dominated the Seto Inland Sea, and attacked and burned the Dazaifu administrative center (the Rebellion of Fujiwara no Sumitomo). Although both uprisings were eventually suppressed, the imperial court found it increasingly difficult to mobilize large-scale military forces on its own and was compelled to rely on the power of local warrior groups to put them down.

Subsequently, a series of regional conflicts continued, including the rebellion of Taira no Tadatsune in 1028, the Former Nine Years’ War (1051–1062), and the Later Three Years’ War (1083–1087). Through these processes, warrior bands rose to prominence as militarily and socially significant actors, eventually paving the way for the establishment of medieval warrior governments.

 

Cloistered Rule (Insei) and the Taira Clan

Because none of Fujiwara no Yorimichi’s daughters became empress or consort, Emperor Go-Sanjō—who had no marital ties to the Fujiwara clan—ascended the throne in 1068. Emperor Go-Sanjō implemented a series of political reforms, issuing the Enkyū Estate Regulation Ordinance and establishing the Office for the Verification of Estate Documents (Kiroku Shōen Kenkeisho) to promote the reorganization of landed estates. He also introduced the senji-masu, an officially sanctioned measuring box, with the aim of standardizing weights and measures.

His successor, Emperor Shirakawa, continued Go-Sanjō’s reformist policies, but in 1086 he abdicated, became a retired emperor, and placed Emperor Horikawa on the throne, thereby initiating cloistered rule (insei). Under this system, the retired emperor exercised direct control over government affairs through inzen (retired-emperor edicts) and the in no chō (cloistered government offices). By organizing systems such as the chigyō-koku (governed provinces), accumulating landed estates, and forming the hokumen no bushi (Northern Palace Guards), the retired emperors established an independent political and economic power base. The system of cloistered rule inaugurated by Retired Emperor Shirakawa was subsequently carried on by Retired Emperors Toba and Go-Shirakawa.

In 1156, following the death of Retired Emperor Toba, conflicts within the imperial family and the regent houses intensified, leading to the Hōgen Rebellion. This was followed in 1159 by the Heiji Rebellion, in which Fujiwara no Nobuyori—who had initially risen to prominence as a close associate of Retired Emperor Go-Shirakawa—deepened his rivalry with the monk Shinzei (Fujiwara no Michinori) and raised troops in support of Emperor Nijō. Shinzei, however, allied himself with Retired Emperor Go-Shirakawa and Taira no Kiyomori to oppose him. Victorious in this conflict, Taira no Kiyomori became the first warrior to enter the core of political power under the cloistered government, and, in cooperation with Retired Emperor Go-Shirakawa, established the Taira regime.

Although relations between Kiyomori and Go-Shirakawa later deteriorated, the Taira clan continued to play a central role in court politics as imperial in-laws. Their regime set an important precedent for warriors assuming a leading role in central government and constituted a crucial preliminary stage in the later establishment of full-fledged warrior governments.

 

Timeline of the Heian period

784	Move of the capital to Nagaoka-kyo
794	Move of the capital to Heian-kyo, progress in the reorganization of the Ritsuryo system
805	Debate on Tokusei (Conflict between Sugano Masamichi and Fujiwara no Otsugu)
810	Rebellion of Kusuko (Retired Emperor Heizei, Fujiwara no Nakanari, and Kusuko vs. Emperor Saga)
842	Jowa Incident (Fall of power of Ban Takemine and Tachibana no Hayataka)
866	Otenmon Incident (Fall of power of Ban Yoshio)
888	Ako Dispute (Fujiwara no Mototsune establishes his position as regent)
899	Fujiwara no Tokihira becomes Minister of the Right
939	Taira no Masakado Rebellion
941	Fujiwara no Sumitomo Rebellion
958	Minting of the Kengen Taiho Coin (One of the Twelve Imperial Coins)
969	Anwa Incident (Demotion of Minamoto no Takaakira, Strengthening of the Fujiwara Clan's Power)
1001–1008	Murasaki Shikibu's The Tale of Genji was written (the height of imperial culture)
1028	Taira Tadatsune's Rebellion (Boso) - suppressed by Minamoto no Yorinobu
1051–1062	Zenkunen no Kabuki (The Abe Rebellion) - suppressed by Minamoto no Yoriyoshi
1069	Enkyu Manor Reorganization Order
1072	Emperor Shirakawa ascends to the throne
1073	Retired Emperor Shirakawa begins cloistered rule (first full-scale cloistered rule)
1083–1087	Gosannen no Kabuki - suppressed by Minamoto no Yoshiie, Fujiwara no Kiyohira rises to power
1087	Emperor Horikawa ascends to the throne (retired Emperor Shirakawa continues his cloistered rule)
1107	Minamoto no Yoshichika's Rebellion - suppressed by Taira no Masamori
1156	Hogen Rebellion (Victory for Emperor Goshirakawa)
1159	Heiji Rebellion (Victory for Taira no Kiyomori)
1167	Taira no Kiyomori becomes Grand Minister of State
1177	Shishigatani Conspiracy (Shunkan, Fujiwara no Narichika, Taira no Yasuyori, and others)
1179	Emperor Goshirakawa is imprisoned (Jisho Coup)
1180	Emperor Mochihito issues an order, Minamoto no Yoritomo raises an army, and Emperor Antoku ascends to the throne
1180–1185	Jisho-Juei Rebellion (Genpei War)
1185	Battle of Dannoura, downfall of the Taira clan

Facilities where you can learn about the Heian period

Gangoji Temple(Nara City, Nara Prefecture)
https://gangoji-tera.or.jp/en/

Muro-ji Temple, “Nyonin Koya” (Uda City, Nara Prefecture)
https://www.murouji.or.jp/en/

Byodoin Temple, World Heritage Site (Uji City, Kyoto Prefecture)
https://www.byodoin.or.jp/en/

Official Miyajima Tourism Website (Hatsukaichi City, Hiroshima Prefecture)
https://www.miyajima.or.jp/english/

Chuson-ji Temple (Hiraizumi Town, Iwate Prefecture)
https://www.chusonji.or.jp/language_en/index.html

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