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 Kanmu, moved the capital of Japan to Heian-kyō (modern Kyoto). means "peace" in Japanese ...

''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, suc ...

located in what is now part of the city of

Ōshū, Iwate is a 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 Maesawa Beef, numer ...

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 (''ken''): Akita, Aomori, Fukushima, Iwate, Miyagi, and Yamagata. Tōhoku ret ...

of far northern

Honshu , historically called , is the largest and most populous island of Japan. It is located south of Hokkaidō across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyūshū across the Kanmon Straits. The island ...

, Japan. 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 CE 710 to 794. Empress Genmei established the capital of Heijō-kyō (present-day Nara, Nara, Nara). Except for a five-year period (740–745), when the capital was briefly moved again, it remai ...

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

Ritsuryō , , is the historical law system based on the philosophies of Confucianism and Chinese Legalism in Japan. The political system in accord to Ritsuryō is called "Ritsuryō-sei" (律令制). ''Kyaku'' (格) are amendments of Ritsuryō, ''Shiki' ...

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

of northern Japan to bring the local

Emishi The (also called Ebisu and Ezo), written with Chinese characters that literally mean "shrimp barbarians," constituted an ancient ethnic group of people who lived in parts of Honshū, especially in the Tōhoku region, referred to as in contemp ...

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 ...

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 corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Ni ...

, 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 and Miyagi Prefectures. The source of the river is the Mount Nanashir ...

. With the defeat of the Emishi chieftain

Aterui (died 21, AD 802 in Enryaku) was the most prominent chief of the Isawa (胆沢) band of Emishi in northern Japan. The Emishi were an indigenous people of North Japan, who were considered hirsute barbarians by the Yamato Japanese. Life Aterui ...

, many of the Emishi tribes in the Shiwa District submitted to Japanese rule. In 803 AD, Shiwa Castle was established in what is now part of the city of

Morioka is the capital city of Iwate Prefecture located in the Tōhoku region of northern Japan. On 1 February 2021, the city had an estimated population of 290,700 in 132,719 households, and a population density of . The total area of the city is . ...

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 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 Yamato 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 in what is now Iwate Prefe ...

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 and the Abe clan in Mutsu Province, in Northeast Japan, from 1051 to 1063. It resulted in Imperial Court victory and ...

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 w ...

of 1083.

Overview

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

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 Buildings and structures completed in 802

History

Overview

See also

References

External links