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
-
Sawayama Castle
During the Kamakura period, Sabo Tokitsuna, the sixth son of Sasaki Sadatsuna, built a fort on Mount Sawayama. This fort occupied a strategically important position because it allowed control over traffic along the important Tōsandō route, which was later known as Nakasendō. This road connected the capital, Kyoto, with the eastern regions of the country. Due to its location, the fortification held great military importance, and during periods of civil war it repeatedly became the site of fierce battles.
-
Nadzima Castle
It is believed that the first structures on this site were built by Tachibana Akitoshi (?-1568), head of the Tachibana clan, a branch family of the Ōtomo clan, as auxiliary fortifications for Tachibanayama Castle. In 1587, Toyotomi Hideyoshi established control over the island of Kyushu and granted Chikuzen Province to Kobayakawa Takakage, one of the leading vassals of the Mori clan. Takakage began construction of a new castle on the site of the existing fortifications in 1588. The exact date of completion is unknown, but by the time the invasion of Korea began in 1592, the castle had already been finished, as records note that Toyotomi Hideyoshi stayed there overnight on his way to Hizen Nagoya Castle, which served as the headquarters of the invasion forces.
-
Kubota Castle
The founder of the castle is considered to be Satake Yoshinobu (1570–1633). Yoshinobu was one of the six great generals of Toyotomi Hideyoshi. During the Odawara Campaign of 1590, he took part in the siege of Oshi Castle under the command of Ishida Mitsunari, with whom Yoshinobu developed a good relationship.
-
Kavanhoe Castle
Kawanoe Castle is located on the small Wasi-yama hill near the port area of the Kawanoe district in the city of Shikokuchuo, occupying a central position along the northern coast of Shikoku Island. Kawanoe was also known as Butsuden Castle. The term “butsuden” in Japan refers to temple halls, and for this reason it is believed that a Buddhist temple once stood on the site before the castle was built. Due to its location at the junction of four provinces on Shikoku Island, Kawanoe held significant strategic importance and was repeatedly targeted by rival forces seeking military control over the region.
-
Yokote Castle
The founder of the castle is considered to be the Onodera clan. The Onodera were originally a minor clan from Shimotsuke Province and served Minamoto no Yoritomo (1147–1199), the founder of the first shogunate. The Onodera distinguished themselves in battle against the Fujiwara clan of the Ōshū branch and were rewarded with lands around Yokote. Around the 14th century, the Onodera moved to Yokote as their permanent residence. Their original stronghold was Numadate Castle, but after a series of clashes with the powerful Nambu clan, they relocated their base to the site of present-day Yokote Castle. It was likely during this time that the first fortifications appeared at the castle.
-
Wakayama Castle
Wakayama Castle was built in 1585, when Toyotomi Hideyoshi ordered his uterine brother, Hashiba (Toyotomi) Hidenaga, to construct a castle on the site of the recently captured Ota Castle. The purpose of this construction was to secure control over the likewise newly conquered Province of Kii. Following an already established tradition, Hidenaga entrusted the project to his castle-building expert, Todo Takatora. Takatora carefully inspected the future castle site, personally drew up several designs, created a model of the planned castle, and took part in the work of laying out the grounds (nawabari). For the construction he brought in more than 10,000 workers and completed the large-scale project within a single year, which was considered extremely fast by the standards of the time.
Toyama Castle
Toyama Castle is located almost in the very center of the former province of Etchū and is surrounded by a wide plain with a large number of rivers. The very first castle on the banks of the Jinzu River was built in 1543 by Jimbo Nagamoto. The Jimbo clan were vassals of the Hatakeyama clan and governed the western part of Etchū Province. The eastern part of the province belonged to their rivals, the Shiina clan, who were also Hatakeyama vassals. Beginning in the 15th century, the influence of the ancient Hatakeyama clan gradually weakened, and as a result, the Jimbo and the Shiina fought constant wars for control of the province. Meanwhile, the forces of the Ikkō-ikki movement periodically intervened, helping first one side and then the other.
Takada Castle
During the Sengoku period, the lands where Takada Castle would later be built were part of Echigo Province and were controlled by the Uesugi clan.
