was an early

Heian period The is the last division of classical Japanese history, running from 794 to 1185. It followed the Nara period, beginning when the 50th emperor, Emperor Kammu, moved the capital of Japan to Heian-kyō (modern Kyoto). means in Japanese. It is a ...

''jōsaku''-style

Japanese castle are fortresses constructed primarily of wood and stone. They evolved from the wooden stockades of earlier centuries and came into their best-known form in the 16th century. Castles in Japan were built to guard important or strategic sites, such a ...

located in what is now part of the city of

Ōshū, Iwate is a Cities of Japan, city located in Iwate Prefecture, Japan. , the city had an estimated population of 114,620 and a population density of 120 persons per km2 in 45,728 households. The total area of the city is . Ōshū is famous for its Maes ...

in the

Tōhoku region The , Northeast region, , or consists of the northeastern portion of Honshu, the largest island of Japan. This traditional region consists of six prefectures (): Akita, Aomori, Fukushima, Iwate, Miyagi, and Yamagata. Tōhoku retains ...

of far northern

Honshu , historically known as , is the largest of the four main islands of Japan. It lies between the Pacific Ocean (east) and the Sea of Japan (west). It is the list of islands by area, seventh-largest island in the world, and the list of islands by ...

Japan Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...

. The site was proclaimed a National National Historic Site in 1922.

History

In the late

Nara period The of the history of Japan covers the years from 710 to 794. Empress Genmei established the capital of Heijō-kyō (present-day Nara). Except for a five-year period (740–745), when the capital was briefly moved again, it remained the capita ...

, after the establishment of a centralized government under the ''

Ritsuryō is the historical Japanese legal system, legal system based on the philosophies of Confucianism and Legalism (Chinese philosophy), Chinese Legalism in Feudal Japan. The political system in accord to Ritsuryō is called "Ritsuryō-sei" (). ''Kya ...

'' system, the imperial court sent a number of military expeditions to what is now the

of northern Japan to bring the local

Emishi The were a group of people who lived in parts of northern Honshū in present-day Japan, especially in the Tōhoku region. The first mention of the Emishi in literature that can be corroborated with outside sources dates to the 5th century AD, ...

tribes under its control. The Emishi were able to successfully resist the Japanese for several decades; however, in 802 AD, the '' Chinjufu-shōgun''

Sakanoue no Tamuramaro was a court noble, general and ''shōgun'' of the early Heian period of Japan. He served as Dainagon, Minister of War and ''Ukon'e no Taisho'' (Major Captain of the Right Division of Inner Palace Guards). He held the ''kabane'' of Ōsukune an ...

led an expedition with 4000 troops from the ten provinces of eastern Japan ( Suruga, Kai, Sagami, Musashi, Kazusa, Shimōsa,

Hitachi () is a Japanese Multinational corporation, multinational Conglomerate (company), conglomerate founded in 1910 and headquartered in Chiyoda, Tokyo. The company is active in various industries, including digital systems, power and renewable ener ...

, Shinano, Kōzuke and Shimotsuke) and built Isawa Castle as his stronghold within Emishi territory in the valley of the

Kitakami River The is the fourth largest river in Japan and the largest in the Tōhoku region. It is long and drains an area of . page 793 It flows through mostly rural areas of Iwate Prefecture, Iwate and Miyagi Prefecture, Miyagi Prefectures of Japan, Pr ...

. With the defeat of the Emishi chieftain Aterui, many of the Emishi tribes in the Shiwa District submitted to Japanese rule. In 803 AD,

Shiwa Castle was an early Heian period ''jōsaku''-style Japanese castle located in what is now part of the city of Morioka, Iwate Prefecture in the Tōhoku region of far northern Honshu, Japan. The site was proclaimed a National Historic Site of Japan in 197 ...

was established in what is now part of the city of

Morioka is the capital Cities of Japan, city of Iwate Prefecture located in the Tōhoku region of northern Japan. On 1 August 2023, the city had an estimated population of 283,981 in 132,719 households, and a population density of . The total area of t ...

to serve as an administrative center of the imperial government. However, the site was prone to flooding, and in 811 AD, and Shiwa Castle was abandoned in favor of

Tokutan Castle was an early Heian period ''jōsaku''-style Japanese castle located in what is now the town of Yahaba in Shiwa District, Iwate Prefecture in the Tōhoku region of far northern Honshū, Japan. The site was proclaimed a National Historic Site of ...

approximately ten kilometers to the south. The garrison at Isawa Castle was reduced to 700 men in 815 AD, of whom many were local Emishi (known as ) in the service of the imperial court. By the middle of the 9th century, mention of Isawa Castle largely disappears from the historical record, although it reappears as a stronghold of

Abe no Munetō was a samurai of the Abe clan during the Heian period of Japan. He was the son of Abe no Yoritoki, the head of the Abe clan of Emishi who were allowed to rule the six Emishi districts in the from Morioka to Hiraizumi, Iwate, Hiraizumi in what ...

in the

Zenkunen War The , also known in English as the Former Nine Years' War or the Early Nine Years' War, was fought between the Imperial Court in Kyoto, Imperial Court and the Abe clan in Mutsu Province, in Tōhoku region, Northeast Japan, from 1051 to 1062. It ...

against the forces central government led by

Minamoto no Yoriyoshi was a Japanese samurai lord who was the head of the Minamoto clan and served as '' Chinjufu-shōgun''. Along with his son Minamoto no Yoshiie, he led the Imperial forces against rebellious forces in the north, a campaign called the Zenkunen War, ...

. It may have been destroyed by the

Gosannen War The Gosannen War (後三年合戦, ''gosannen kassen''), also known as the Later Three-Year War, was fought in the late 1080s in Japan's Mutsu Province on the island of Honshū. History The Gosannen War was part of a long struggle for power ...

of 1083.

Overview

Excavation research revealed that Isawa Castle was a square castle surrounded by double moat and wooden

palisade A palisade, sometimes called a stakewall or a paling, is typically a row of closely placed, high vertical standing tree trunks or wooden or iron stakes used as a fence for enclosure or as a defensive wall. Palisades can form a stockade. Etymo ...

measuring 670 meters on each side and thus enclosing an area of 460,000 square meters. At the center was a government office complex in a separate enclosure, with dimensions of 90 meters on each side. The site is located about 15 minutes by bus from

Mizusawa Station Wind chimes at the Mizusawa Station platform is a railway station in the city of Ōshū, Iwate Prefecture, Japan, operated by East Japan Railway Company (JR East). Lines Mizusawa Station is served by the Tōhoku Main Line, and is located fr ...

on the

JR East The is a major passenger railway company in Japan and the largest of the seven Japan Railways Group companies. The company name is officially abbreviated as JR-EAST or JR East in English, and as in Japanese. The company's headquarters are in ...

Tohoku Main Line.

References

External links

Iwate Prefectural Agency for Cultural Affairs

Oshu city official home page
{{in lang, ja 9th-century establishments in Japan Castles in Iwate Prefecture Ruined castles in Japan History of Iwate Prefecture Heian period Ōshū, Iwate Archaeological sites in Japan Historic Sites of Japan 802 establishments 9th-century fortifications

History

Overview

See also

References

External links