Nirayama Castle -History of Hojyo clan for 100 years of five generations-

Nirayama Castle

-History of Hojo clan for 100 years of five generations-

Overview

Name: Nirayama castle (Nirayama-jo)
Alias:
Place: Nirayama Izunokuni city, Shizuoka
Type: Hill castle / Mountain castle
Built: Originally 15th century, expanded in 16th century
Remaining remnants: Clay walls and dry moats
Title:

Brief History

Nirayama castle (韮山城) is located at a long and narrow hill at Izunokuni city, at the root of Izu peninsula. This area is famous as a place of exile where Yoritomo Minamoto (1147-1199), the first shogun of Kamakura Shogunate was sent in his childhood.

Nirayama castle is built in 15th century. In 1457, Yoshimasa Ashikaga (1436-1490), eighth shogun of Muromachi Shogunate, appointed his brother Masatomo Ashikaga (1435-1491) as a representative of Shogunate in Kanto area. But obstructed by local lords he could not enter the Kanto area, and located at Horikoshi palace near Nirayama castle and called as Horikoshi highness.

Souun Hojo, the first leader

In 1495, utilizing internal conflict of Nirayama highness house, Nagauji Ise (1432-1519), who later called as Soun Hojyo, captured Nirayama castle. Nagauji was originally a general of Imagawa clan, a house of governor of Suruga province (eastern part of Shizuoka prefecture), but Souun seized Izu province (Izu peninsula area) in three years and became an independent warlord. He used Nirayama castle as his residence, but in 1495 Soun occupied Odawara castle in Sagami province (Kanagawa prefecture) and moved to there. Soun finally expanded his territory into Miura peninsula, at the middle of Sagami province, and died in 1519.

Ujitsuna Hojo, the second leader

During the second leader Ujitsuna Hojyo (1487-1541), Hojyo clan captured most part of Sagami province, utilizing the conflict between Koga Kubo and Koyumi Kubo, two traditional representative house of Muromachi shogunate in Kanto, and also Yamanouchi Uesugi clan and Ogigayatsu Uesugi clan. Ujitsuna also renamed their surname from Ise to Hojo, the name of the house of chancellor in Kamakura shogunate, to appeal their legitimacy to dominate Kanto region (to distinguish from Hojyo clan in Kamakura period, this Hojo clan is sometimes called as later Hojyo clan). But at the last years of Ujitsuna, fearing rapid expansion of Hojo clan, these old powers united and started to counter attack to Hojo clan.

Ujiyasu Hojo, the third leader

At the period of third leader Ujiyasu Hojyo (1515-1571), ally of old powers attacked Kawagoe castle and Hojo clan became its crisis. In response to this, making peace with Imagawa clan under the support of Takada clan (later lead to triangle treaty) to make safe in backward, Ujiyasu made sudden night attack against sieging large army of old houses. Hojo clan perfectly won this battle, and seized the hegemony in Kanto region.

Later Ujiyasu extinguished Ogigayatsu Uesugi clan and expelled Yamanouchi Uesugi clan, expanded its territory all over Musashi country (Tokyo metropolis and Saitama prefecture) by 1551. Suffered from continuous assault by Kenshin Uesugi (1530-1578), a governor of Echigo country (Niigata prefecture) and who supported Yamanouchi Uesugi clan, coordinating with Shingen Takeda (1521-1573), a warlord of Kai country (Yamanashi prefecture), Hojyo clan further pushed up its border into Kozuke country (Gunma prefecture). Ujiyasu also fought with Satomi clan, a governor of Awa country (Boso peninsula), and also seized western half of Kazusa country (Chiba prefecture).

Ujimasa Hojo, the fourth leader

Ujimasa Hojo (1538-1590) was the fourth leader of Hojyo clan. Ujimasa appointed his three brothers as regional commander, it means Ujinori Hojyo (1545-1600) managed Izu region at Nirayama Castle, Ujiteru Hojyo (1540-1590) managed eastern Kanto region at Takiyama Castle (Tokyo metropolis) and Ujikuni Hojyo (1541-1597) managed northern Kanto region at Hachigata castle (Saitama prefecture).

Supported by these brothers, Ujimasa forced local lords such as Satomi clan, Utsunomiya Clan or Yuki clan to subordinate to them, and its sphere of influence expanded to almost all part of Kanto region, except for Hitachi province (Ibaraki prefecture) governed by Satake clan, and north part of Kozuke province seized by Takeda clan and Sanada clan. But in this time, the power of central Japan started to reach to Kanto region. Once Ujimasa had to subordinate to Nobunaga Oda (1534-1582), the ruler of central era, and after the death of Nobunaga, his successor Hideyoshi Toyotomi (1537-1598) made pressure to Hojyo clan.

Ujinao Hojyo, the last leader

Ujinao Hojo (1538-1590), the last leader of Hojo clan, succeeded his position at xx. Under the coordination of Ieyasu Tokugawa (1543-1616), his father in law, Hojo clan seemed to make peace with Toyotomi government, but due to the capture of Nagurumi castle at 1591, Toyotomi government started Odawara campaign against Hojo clan with over 200,000 troops. Attacked by dominant army of Toyotomi side, Hojo clan was besieged at Odawara castle but surrendered in 1590, and the history of Hojo clan as a ruler of Kanto region became an end.

Finally extinguished by central power, but administration of Hojo clan was said to be quite organized and fair. There was no internal conflict for the position of leader, because each leader lived long and could succeed their position to his son with fully preparation, and also continuous expansion enabled to allocate sufficient territory to each relatives.

In military sphere, Hojyo clan effectively mobilized soldiers from its retainers and built excellent castles, and expanded its territory in the long run in spite of some defeats in individual battle.

Nirayama castle on and after Odawara campaign

Concerning Nirayama castle, after the movement to Odawara castle, Nirayama castle had been used as a center of Izu province and a main base of armies in western area. At the time of Odawara campaign in 1590, Nirayama castle was surrounded by 50,000 army of Toyotomi side, but Ujinori Hojo, the commander of the castle, stand for four months with only hundreds soldiers. Finally he surrendered to Ieyasu Tokugawa, and his descendant continued as a feudal lord in Edo period.

After the campaign Nirayama castle had been used for a while, but abolished in the beginning or Edo era. Next to the site of the castle, the residence of Egawa clan, a house of local magistrate of this area appointed by Edo shogunate, still remains well.