Kiyosu Castle -Place of important alliance and conference

Kiyosu Castle

-Place of important alliance and conference-

Overview

Name: Kiyosu castle (Kiyosu-jo)
Alias:
Place: Asahi-Shiroyashiki Kiyosu city, Aichi

Location: 35.21770213960986, 136.84187853894517
Type: Flat castle
Built: Originally beginning of 16th century, expanded in late 16th century
Remaining remnants: Stone walls (moved)
Title:

Brief History

Kiyosu castle (清洲城) is located in Kiyosu city at the northwest from Nagoya city. Being placed at the side of Gojyo river, Connected to Iwakura castle, a center of upper Owari province (western part of Aichi prefecture) and Tsushima port, an economic center of Owari by Gojyo river, Kiyosu castle has been a center of lower Owari province throughout 16th century.

Kiyosu castle was originally built by Shiba clan, a governor of Owari province at the beginning of 16th century. But the governance of Shiba clan was nominal, and Owari country was substantially dominated by Iwakura Oda clan, placed at Iwakura castle and held upper half of Owari province, and Kiyosu Oda clan, located in Kiyosu castle with Shiba clan and kept lower half of Owari province. Nobuhide Oda (1510-1551), father of Nobunaga Oda (1534-1582), was originally a vessel of Kiyosu Oda clan.

After the death of Nobuhide, in 1554, Nobutomo Oda (?-1555), leader of Kiyosu clan, killed Yoshimune Shiba (1513-1554), current governor of Owari province in Kiyosu castle. In response to this, Nobunaga assaulted Nobutomo as a revenge of Yoshimune and captured Kiyosu castle. After that, until his movement to Komakiyama castle in 1563, Nobunaga stayed Kiyosu castle as his residence.

Kiyosu Alliance

In 1560, Nobunaga beat and killed Yoshimoto Imagawa (1520-1560), a warlord of Suruga province (middle part of Shizuoka prefecture) who invaded to Owari province. Matsudaira clan, a warlord of Mikawa province (eastern part of Mikawa prefecture) which subordinated to Imagawa clan, became independent taking opportunity.

In 1562, Motoyasu Matsudaira (1543-1616), leader of Matsudaira clan at Okazaki castle and who later became the founder of Edo shogunate as Ieyasu Tokugawa, came to Kiyosu castle and made an alliance with Nobunaga. This alliance is called as "Kiyosu Domei", it means Kiyosu alliance.

Rarely in the Sengoku era, this treaty was effective for 20 year until the death of Nobunaga at the accident of Honnoji in 1582. Other than keeping their backwards safe, Ieyasu supported Nobunaga at the battles against surrounding enemies to seize his hegemony, and Nobunaga extinguished Takeda clan which made pressures to Tokugawa clan.

At the last moment Nobunaga’s power significantly exceeded Ieyasu and Ieyasu virtually became a retainer of Nobunaga, but this treaty had been effective for both side throughout its period (Contrary to his fierce image, Nobunaga did not break any treaty from his side and was only broken. Other warlords such as Shingen Takeda (1521-1573, a warlord of Kai province (Yamanashi prefecture) had the record of frequent break of treaty).

Kiyosu Conference

In May 1582, Nobunaga and his successor Nobutaga Oda (1555-1582) died at the accident of Honnoji, a coup d’etat by his regional commander Mitsuhide Akechi (1528-1582). After Hideyoshi Hashiba (1537-1598, later Hideyoshi Toyotomi) broke Mitsuhide at the battle of Yamazaki 10 days after the accident, there was a conference among survived relatives and major commanders to decide new structure of Oda clan at Kiyosu castle in June.

At the conference, Nobutaka Oda (1558-1583), third son of Nobunaga and commander of Kanbe castle, aimed to succeed the leader of Oda clan with Katsuie Shibata (1522-1583), an old general of Nobunaga and commander of Hokuriku region. But Hideyoshi cooperated with other powerful general Nagahide Niwa (1535-1585) and insisted Hidenobu Oda (1580-1605), a son of Nobutada, was a legitimate successor of Oda clan under the guardianship of Hideyoshi.

As Hideyoshi lead and succeded the revenge to Mitsuhide, he could won the point and became the leading person of Oda clan. Mino province and Owari province, direct territories of Oda clan were divided into Nobutaka and Nobukatsu Oda (1558-1630), the second son of Nobunaga, and it was decided that princess Oichi, younger sister of Nobunaga, married with Katsuie. Next year Hideyoshi excluded resistance of Nobutaka and Katsuie at the battle of Shizugatake, and took over the hegemony of Oda clan.

Afterward of the castle

After the conference Kiyosu castle was held by Nobukatsu, and he transformed this castle into a modern one with stone walls, water moats and main towers. But in 1590, Nobukatsu was confiscated his territory by Hideyoshi and in 1595, Masanori Fukushima (1561-1624) was appointed as a commander under Toyotomi government.

Masanori was born at the same province as Hideyoshi, and a courageous general known as one of the seven braves at Shizugatake. Hideyoshi placed Masanori expecting to hold back attack of Ieyasu Tokugawa (1543-1616) , the largest lords placed in Kanto region. But after the death of Hideyoshi in 1598, due to a conflict with Mitsunari Ishida (1560-1600), a chief administrative staff of Hideyoshi, Masanori supported Ieyasu at the battle of Sekigahara in 1600.

After the battle of Sekigahara Masanori was transferred Hiroshima castle at Aki province (Hiroshima prefecture) with larger territory, and Ieyasu placed Yoshinao Tokugawa (1601-1650), his ninth son as a lord of Owari province. At first Yoshinao lived at Kiyosu castle, but due to weak ground next of river and surrounding existing towns, Kiyosu castle had no room for expansion.

As Tokugawa clan needed secure castle considering Hideyori Toyoromi (1593-1615), a son of Hideyoshi located at Osaka castle, Ieyasu decided to build Nagoya castle instead of Kiyosu castle. Buildings and materials of Kiyosu castle was used to build Nagoya castle, and after the completion, all samurais and merchants lived in Kiyosu were forced to move to Nagoya. The site of Kiyosu castle turned into a wasteland, but was still managed by Owari domain throughout Edo era.

Subsequent to Meiji revolution, most part of the site of the castle was lost due to development, and former central area was divided by railway. But the ruin of basement of main tower slightly remains, and a main tower was like building is built at the opposite side of Gojyo river and used as a castle museum.

Access

20 minute walk from JR Central Tokaido-Honsen line Kiyosu station or 15 minutes walk from Meitetsu Honsen line Shinkiyosu station. 15 minutes drive from Nagoya Daini-Kanjo Expressway Kiyosu-nishi interchange.