Iwasaki Castle, often overlooked in history books and tourist guides, is located in modern-day Nisshin City, approximately 15 kilometers southeast of Nagoya City. Positioned on a hill, it offers clear views of the surrounding plain.
The castle is believed to have been built by Oda Nobuhide, father of Oda Nobunaga, in the early 16th century to protect his eastern borders and support his base at nearby Shobata Castle. In 1529, Matsudaira Kiyoyasu, Tokugawa Ieyasu’s grandfather, seized the castle by force. Six years later, Kiyoyasu was killed by one of his retainers during a misunderstanding, and his son, Matsudaira Hidetada (Ieyasu’s father), entrusted the castle to Niwa Ujikiyo.
Iwasaki Castle played a significant role in the Battle of Komaki and Nagakute in 1584. Ikeda Tsuneoki led the Toyotomi Hideyoshi forces against the Tokugawa-held castle. The Toyotomi strategy aimed to bypass Tokugawa lines and attack Ieyasu’s stronghold at Okazaki, making quick strikes on small castles along the way to confine them. However, at Iwasaki Castle, Ikeda’s forces were fired upon, and Tsuneoki himself was shot, falling from his horse. Enraged and humiliated, he commanded a full-scale assault. Despite a strong defense, the castle fell with heavy casualties, including over 300 dead. This delay allowed Ieyasu’s forces to catch up and defeat the Toyotomi at the Battle of Nagakute.
The Niwa clan held the castle for nearly 60 years until the Battle of Sekigahara in 1600, after which they were awarded a castle in present-day Toyota City, leading to Iwasaki’s abandonment. Reconstructed in concrete in 1987, the castle is now surrounded by two hectares of preserved parkland. Despite its visual appeal, the reconstruction is not historically accurate. An excavation revealed the remains of a well and a lookout tower. The structure below the keep now houses a museum dedicated to the history of the castle, the battle, and the Niwa clan.
See also
-
Amagasaki Castle
The founding year of Amagasaki Castle is traditionally considered to be 1617, when Toda Ujikané built his castle here, making it the administrative center of the Amagasaki Domain. However, as early as the Sengoku period, a fortress built by the Hosokawa clan already stood on this site. After the fall of Itami Castle in 1579, Araki Murashige—formerly a vassal of Oda Nobunaga who had rebelled against him—fled to this earlier castle.
-
Hiroshima Castle
Mōri Terumoto (1553–1625) was the grandson and rightful heir of the renowned Mōri Motonari. When Terumoto became the head of the Mōri clan in 1571, he inherited vast territories covering a large part of the San’in and San’yō regions in western Honshū. In addition, the Mōri clan possessed the largest and most technologically advanced naval fleet of its time.
-
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.
