was a daimyo

Daimyo

is a generic term referring to the powerful territorial lords in pre-modern Japan who ruled most of the country from their vast, hereditary land holdings...

 in Azuchi-Momoyama period

Azuchi-Momoyama period

The came at the end of the Warring States Period in Japan, when the political unification that preceded the establishment of the Tokugawa shogunate took place. It spans the years from approximately 1573 to 1603, during which time Oda Nobunaga and his successor, Toyotomi Hideyoshi, imposed order...

, and one of the Go-Bugyō

Go-Bugyo

The or Five Commissioners, was an administrative organ of feudal Japan which later evolved into the Go-Tairō . It was established by Toyotomi Hideyoshi when he became kampaku in 1585....

appointed by Toyotomi Hideyoshi

Toyotomi Hideyoshi

was a daimyo warrior, general and politician of the Sengoku period. He unified the political factions of Japan. He succeeded his former liege lord, Oda Nobunaga, and brought an end to the Sengoku period. The period of his rule is often called the Momoyama period, named after Hideyoshi's castle...

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Also called Niemon (仁右衛門) or by his court title, Uemon-no-jō (右衛門尉).

Nagamori was born in Nakashima-no-kori, Mashita-mura, Owari Province

Owari Province

was an old province of Japan that is now the western half of present day Aichi Prefecture, including much of modern Nagoya. Its abbreviation is Bishū .-History:The province was created in 646....

 or Asai-gori, Mashita-go, Ōmi Province

Omi Province

is an old province of Japan, which today comprises Shiga Prefecture. It was one of the provinces that made up the Tōsandō circuit. It is nicknamed as .Lake Biwa, Japan's largest lake, is located at the center of the province...

 and served Hashiba Hideyoshi (Toyotomi Hideyoshi

Toyotomi Hideyoshi

was a daimyo warrior, general and politician of the Sengoku period. He unified the political factions of Japan. He succeeded his former liege lord, Oda Nobunaga, and brought an end to the Sengoku period. The period of his rule is often called the Momoyama period, named after Hideyoshi's castle...

) when he had been a retainer of Oda Nobunaga

Oda Nobunaga

was the initiator of the unification of Japan under the shogunate in the late 16th century, which ruled Japan until the Meiji Restoration in 1868. He was also a major daimyo during the Sengoku period of Japanese history. His opus was continued, completed and finalized by his successors Toyotomi...

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Since he shined with domestic affairs such as Cadastral Surveys by Hideyoshi and diplomatic negotiations with Uesugi Kagekatsu

Uesugi Kagekatsu

was a daimyo during the Sengoku and Edo periods of Japanese history. The son of Nagao Masakage and husband of Uesugi Kenshin's elder sister, Aya-Gozen. After his father died, he was adopted by Kenshin....

, Hideyoshi gave him 200,000 koku

Koku

The is a Japanese unit of volume, equal to ten cubic shaku. In this definition, 3.5937 koku equal one cubic metre, i.e. 1 koku is approximately 278.3 litres. The koku was originally defined as a quantity of rice, historically defined as enough rice to feed one person for one year...

 at Koriyama Castle, Yamato Province

Yamato Province

was a province of Japan, located in Kinai, corresponding to present-day Nara Prefecture in Honshū. It was also called . At first, the name was written with one different character , and for about ten years after 737, this was revised to use more desirable characters . The final revision was made in...

 and appointed him to five bugyo.
Nagamori took part in the Battle of Bunroku (in 1592) and the Battle of Keicho (in 1596).

After Hideyoshi died, in 1600, Nagamori took part in Ishida Mitsunari

Ishida Mitsunari

Ishida Mitsunari was a samurai who led the Western army in the Battle of Sekigahara following the Azuchi-Momoyama period of the 17th century. Also known by his court title, Jibunoshō...

's force when he put up Mōri Terumoto

Mori Terumoto

Mōri Terumoto , son of Mōri Takamoto and grandson and successor of the great warlord Mōri Motonari, fought against Toyotomi Hideyoshi but was eventually overcome, participated in the Kyūshū campaign on Hideyoshi's side and built Hiroshima Castle, thus essentially founding Hiroshima.Terumoto was a...

 who was a member of the council of Five Elders

Council of Five Elders

The council of five elders, also known as the five Tairō , was formed by Toyotomi Hideyoshi to rule Japan in the place of his son, Hideyori, until such time as he came of age. Hideyoshi chose his five most powerful daimyo: Ukita Hideie, Maeda Toshiie, Uesugi Kagekatsu, Mōri Terumoto, and the...

 and raised their army to Tokugawa Ieyasu

Tokugawa Ieyasu

 was the founder and first shogun of the Tokugawa shogunate of Japan , which ruled from the Battle of Sekigahara  in 1600 until the Meiji Restoration in 1868. Ieyasu seized power in 1600, received appointment as shogun in 1603, abdicated from office in 1605, but...

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However, Nagamori was involved in an intrigue with Ieyasu.
He didn't take part in the Battle of Sekigahara

Battle of Sekigahara

The , popularly known as the , was a decisive battle on October 21, 1600 which cleared the path to the Shogunate for Tokugawa Ieyasu...

 on October 21 and held a fort at Osaka Castle

Osaka Castle

is a Japanese castle in Chūō-ku, Osaka, Japan.Originally called Ozakajō, it is one of Japan's most famous castles, and played a major role in the unification of Japan during the sixteenth century of the Azuchi-Momoyama period.-Description:...

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After the Battle, Ieyasu seized Nagamori's domain, but helped his life and left him to Kōriki Kiyonaga

Koriki Kiyonaga

was a Japanese daimyo during the Azuchi-Momoyama period and Edo periods. A native of Mikawa Province, Kiyonaga served the Tokugawa clan during its battles, until 1600....

 who was a retainer of Ieyasu and lord of Iwatsuki Castle, Musashi Province

Musashi Province

was a province of Japan, which today comprises Tokyo Prefecture, most of Saitama Prefecture and part of Kanagawa Prefecture. It was sometimes called . The province encompassed Kawasaki and Yokohama...

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In 1615 at Siege of Osaka

Siege of Osaka

The was a series of battles undertaken by the Tokugawa shogunate against the Toyotomi clan, and ending in that clan's destruction. Divided into two stages , and lasting from 1614 to 1615, the siege put an end to the last major armed opposition to the shogunate's establishment...

, Nagamori's son Mashita Moritsugu, who had served to Tokugawa Yoshinao

Tokugawa Yoshinao

was a Japanese daimyo of the early Edo period.- Biography :Born as the ninth son of Tokugawa Ieyasu, his childhood name was Gorōtamaru. While still a young child, he was appointed leader of first the fief of Kofu in Kai Province and later the fief of Kiyosu in Owari Province...

, escaped and took part in
Toyotomi Clan

Toyotomi clan

Originating in Owari Province, the served as retainers to the Oda clan throughout 16th-century Japan's Sengoku period. -Unity and Conflict:The most influential figure within the Toyotomi was Toyotomi Hideyoshi, one of the three "unifiers of Japan." Oda Nobunaga was another primary unifier and the...

's force.
As a result, Nagamori was commanded to commit suicide. He died at 71.

His grave is at Anraku-ji, Niiza, Saitama

Niiza, Saitama

is a city located in Saitama Prefecture, Japan, and is essentially a suburb of the Tokyo conurbation. Niiza is located at the southernmost part of Saitama. As of 2010, the city has an estimated population of 159,741 and a population density of 7,010 persons per km²...

, Saitama Prefecture

Saitama Prefecture

is a prefecture of Japan located in the Kantō region of the island of Honshu. The capital is the city of Saitama.This prefecture is part of the Greater Tokyo Area, and most of Saitama's cities can be described as suburbs of Tokyo, to which a large amount of residents commute each day.- History...

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