Kiyosu Castle was initially constructed around 1405 by Shiba Yoshishige, the Governor of Owari, serving as a major strategic defense and later as the seat of power for the Owari region (now Aichi Prefecture). One branch of the Oda clan, administrators of Owari, took control of southern Owari and Kiyosu Castle from 1476, while the other branch was based in Iwakura Castle, overseeing northern Owari.
Kiyosu Castle was the launch point for many significant samurai battles during the turbulent Sengoku, or Warring States Period (1450-1615), including the battles of Okehazama (1560), Anegawa (1570), Nagashino (1575), and Sekigahara (1600).
In 1555, after the death of his father, Oda Nobunaga enlisted the help of his uncle, Oda Nobumitsu, to attack and kill Oda Nobutomo, the clan leader at Kiyosu Castle. Nobunaga subsequently relocated from Nagoya Castle to Kiyosu. Two years later, he discovered a plot by his younger brother, Nobuyuki, to overthrow him. Feigning illness, Nobunaga drew Nobuyuki close and assassinated him within Kiyosu Castle, thereby eliminating opposition and ensuring clan stability.
Kiyosu remained Nobunaga’s base for many years, during which time the city flourished due to his economic reforms and enhanced security. The castle grounds once spanned 1.6 kilometers east-west and 2.8 kilometers north-south, featuring an outer, central, and inner moat system.
On July 16, 1582, just weeks after Nobunaga’s death at Honno-ji Temple in Kyoto, an important meeting regarding the Oda clan’s succession, known as the Kiyosu Conference, was held at Kiyosu Castle. Top Oda retainers, including Shibata Katsuie, Toyotomi Hideyoshi, Niwa Nagahide, and Ikeda Tsuneoki, gathered to decide on Nobunaga’s successor. With Nobunaga’s designated heir, Nobutada, having died at Nijo Castle, the succession was contested between Toyotomi Hideyoshi, who supported Oda Samboshi (Nobunaga’s infant grandson), and Shibata Katsuie, who backed Nobunaga’s third son, Nobutaka. The conference ended without resolution, leading to escalating tensions between Hideyoshi and Katsuie, culminating in the Battle of Shizugatake. Ultimately, Hideyoshi triumphed, leading to Katsuie’s defeat and suicide, and Hideyoshi's eventual domination of Japan.
Following the Battle of Sekigahara in 1600, Kiyosu Castle saw various masters. It was reconstructed in concrete in 1989 across a small river from its original location. The actual site of the keep now features the "Kiyosu Furusato no Yakata," a small rest area and souvenir stall. Surprisingly, the JR train lines and Bullet Train lines run directly through the old castle site. The southern half of Kiyosu Castle is now a park with statues of Oda Nobunaga in full armor and his wife, Princess No-Hime.
The current reconstructed Kiyosu Castle serves as a symbol of Kiyosu City and houses a well-planned museum featuring fascinating displays and artifacts related to the castle’s history and its role in the Period of Warring States.
See also
-
Fukuyama Castle
After the defeat of Toyotomi Hideyori’s supporters in the Osaka Campaigns of 1614–1615, many clans in Japan still remained not fully loyal to the Tokugawa shogunate, especially in the western Chūgoku region. Mizuno Katsunari (1564–1651), a cousin of Tokugawa Ieyasu, became the first of the Tokugawa house’s close retainers, the so-called fudai daimyō, to be relocated to this strategically important area.
-
Tiba Castle
The founder of the Chiba clan is considered to be Chiba Tsunesige (1083–1180), who in 1126 moved his residence to the Inohana area and built a strongly fortified stronghold there. Although Tsunesige himself came from the Taira clan, the Chiba clan later supported Minamoto no Yoritomo, the future founder of the first shogunate.
-
Sunomata Castle
Oda Nobunaga, as part of his “final solution” to the conflict with the Saitō clan, conceived the construction of a fort in the Sunomata area, which was intended to serve as a forward base for an attack on Inabayama Castle (later renamed Gifu). Sunomata was a swampy area located between Ogaki Castle, a stronghold of the Oda clan, and Inabayama, the main fortress of the Saitō clan. Earlier attempts to build fortifications in this area, carried out by Oda generals Sakuma Nobumori and Shibata Katsuie, had all ended in failure. After that, the task was entrusted to the young vassal Kinoshita Tokichirō, who later became known as Toyotomi Hideyoshi.
-
Shibata Castle
The exact time when structures first appeared on the site of the present-day castle is unknown; however, it is generally believed that the first fortified buildings were constructed here during the Muromachi period, when these lands were controlled by the Shibata clan.
-
Okayama Castle
According to a number of accounts, the earliest fortifications on the site of present-day Okayama Castle appeared as early as the 14th century and were built by the Nawa clan. The Asahigawa River was used as a natural defensive barrier, protecting one side of the fortifications.
In the early 16th century, the Kanamitsu clan constructed a new castle here, which at the time was known as Ishiyama. In 1573, it came under the control of the Ukita clan, after which Ukita Naoie (1529–1582) launched large-scale reconstruction efforts. He did not live to see the work completed, and construction was continued by his son Hideie. -
Nagahama Castle
Hashiba, later known as Toyotomi Hideyoshi, received Odani Castle and the surrounding lands from Oda Nobunaga after the defeat of the Azai clan. However, Odani Castle was located high in the mountains, which made it poorly suited for the effective administration of the territory. For this reason, in 1575 Hideyoshi began constructing a new castle in the village of Imahama on the shore of Lake Biwa. Taking the character naga from Nobunaga’s name, he renamed both the village and the new castle Nagahama.
-
Kokura Castle
Kokura Castle is traditionally considered to have been founded by Hosokawa Tadaoki (1563–1645), although by the time the Hosokawa clan came to control these lands, the fortification had already existed since at least 1569 and was most likely built by members of the Mori clan.
-
Ikeda Castle
In 1334, Ikeda Noriyoshi built a small fort on this site, which over time was repeatedly expanded and rebuilt. During the Ōnin War of 1467–1477, the Ikeda clan supported the Western Coalition. As a result, Ikeda Castle was attacked and captured by the forces of the Eastern Coalition, but it was soon recaptured, allowing it to avoid serious destruction.
