Nagashino castle – 日本200名城バイリンガル (Japan's top 200 castles and ruins)

118.Oshi Castle Part1

Tins castle is known for the Battle of Oshi Castle.

Location and History

Narita Clan builds Castle using Marshes between rivers

Gyoda City is located in the northern part of Saitama Prefecture, which is sandwiched by two large rivers in the Kanto Region, Tonegawa and Aarakawa Rivers. The land of the city is very flat and has been developed for living comfortably, however, it was marshy and waterlogged in the Middle Ages due to its terrain and flood from the rivers. The Narita Clan governed the area, which was called Oshi, in the 15th and 16th Centuries during the Sengoku Period. It is said that the clan first built Oshi Castle in the late 15th Century. Many battles happened in the Kanto Region at that time, so local lords needed to protect themselves by building strong castles. Some built mountain castles such as Minowa Castle for the Nagano Clan and Kanayama Castle for the Iwamatsu Clan. On the other hand, the Narita Clan’s choice was to build a Water Castle, using the area’s features of islands among the marshes and natural levees along the rivers. The castle’s enclosures were connected by paths on bridges and earthen walls.

The range of Gyoda City and The location of the castle

The strength of the castle was actually proven when Hideyoshi Toyotomi invaded the Kanto Region to complete his unification of Japan in 1590. The whole region had been governed by the Hojo Clan which the Narita Clan served then. The Hojo Clan ordered their branches including Oshi Castle to gather soldiers to their home base, Odawara Castle to against Hideyoshi. Ujinaga Narita, the lord of Oshi Castle had to leave it for Odawawa, so few defenders were left in the castle, under the castle keeper, Nagachika Narita, Ujinaga’s cousin. Hideyosi attacked the Hojo’s territory with over 200,000 soldiers, sending troops to not only Odawara Castle but also branch castles. For example, Kanayama Castle where a magistrate from the Hojo governed was easily open by the troops. However, the only 500 defenders with 2500 residents in Oshi castle, instructed by Nagachika, never surrendered against over 20,000 attackers.

Castle is attacked by Inundation tactics in Battle of Oshi Castle

The Portrait of Hideyoshi Toyotomi, attributed to Mitsunobu Kano, owned by Kodaiji Temple (licensed under Public Domain via Wikimedia Commons)

The commander head of the attackers was Mitsunari Ishida, a highly trusted retainer from Hideyoshi, who was also supported by other lords, such as Nagamasa Asano and Masayuki Sanada. Hideyoshi was not there, but he ordered Mitsunari to flood the castle by making banks surrounding it to keep more water. His idea probably came from the geographical features and his successful experience of the Battle of Bicchu-Takamatsu Castle where he did the same way. It is said that Mitsunari put his strong hold on Maruhakayama-Kofun, an Ancient Burial Mound, about 2km away from the castle in the south. His team rapidly built 15 to 25 km banks around the mound in few days to dam water from the rivers. A folk story remains that farmers were asked to bring earth bags to build banks for a high fee.

The portrait of Mitsunari Ishida, owned by Hajime Sugiyama (licensed under Public Domain via Wikimedia Commons)

The partially remaining bank Mitsunari built, called Ishida Tsutsumi

It is uncertain if his attempt was successful according to some records in which the defenders secretly cut part of the banks to drain water drowning some attackers. The fact is that when the supporting lords tried to assault the castle, Hideyoshi ordered them to stop it and continue the inundation. The siege lasted for about a month, however, the castle couldn’t be beaten until the master Hojo surrendered in Odawara Castle. The castle has been nicknamed “a floating castle” of “a turtle castle” which probably originate from what the castle looked like in the siege.

“The illustration of the Narita Clan’s Oshi Castle during the Tensho Era”, it was made by a local historian to consider the Battle of Oshi Castle during the Meiji Era, exhibited by the Gyoda City Local Museum

The Horikiri-bashi Bridge where the bank was cut according to a local tradition

Castle becomes important defense site for Edo

In the Edo Period, Oshi Castle was governed by relatives or hereditary vassals of the shoguns as the Oshi Domain. This was because this castle was located in an important defensive site for Edo Castle, the shogun’s home base in the south. It is said that the Abe Clan, which often became members of shogun’s council of elders, completed the castle. They still used the basic structures of the castle as the island-like enclosures among the moats and marshes. However, they improved the castle’s defense systems more by building the three-level turret (similar to the Main Tower), other turrets and gates. The castle and domain were finally followed by the Okudaira-Matsudaira Clan, whose origin was the son of Nobumasa Okudaira who contributed to Ieyasu Tokugawa, the founder of the shogunate, in the Battle of Nagashino Castle and was married with Ieyasu’s daughter. They were trusted in and ordered by the shogunate to guard the No.3 Shinagawa Battery facing Edo Bay to prepare for possible threat to Western battleships at the end of the Edo Period.

The miniature model of Oshi Castle during the Edo Period, exhibited by the Gyoda City Local Museum

The rebuilt three-level turret of Oshi Castle, it was built in a different position from the original one

To be continued in “Oshi Castle Part2”

38.Iwamura Castle Part1

A great mountain castle with a sad episode

Location and History

One of Three Great Mountain Castles

Iwamura Castle was a large mountain castle which was located in the eastern part of Mino Province (now Gifu Prefecture). The castle has been considered as one of the Three Great Mountain Castles followed by Bicchu-Matsuyama and Takatori Castles. Basically, mountain castles were built during the Sengoku Period when many battles happened. However, during the peaceful Edo Period, most castles were moved or rebuilt on plain land for the governor. The Three Great Mountain Castles were rare examples which remained until the end of the Edo Period. In particular, Iwamura Castle had the highest altitude of 717 meters high among the active castles during that time.

The location of the castle

The relief map around the castle

Female Lord, Otsuya and her Tragedy

It was said that the Toyama Clan first built the castle in the 13th Century, but it is quite uncertain. Records show the clan used the castle as their home base in the first 16th Century during the Sengoku Period. The Toyama Clan was one of the local warlord families residing in the area, which became the head of the local lord group called the Iwamura Group. However, the clan was affected by other larger warlords such as the Takeda and Oda Clans. For example, the clan often worked for the Takeda Clan. They often married their wife who belonged to the Oda Clan. This was to ensure balance between the two clans. In 1571, when a lord of the castle died, Nobunaga Oda sent one of his sons as the next lord of the Toyama Clan. The ex-lord’s wife named Otsuya, who came from Oda and Nobunaga’s aunt, actually governed the castle because the new lord was still very young. She has been known as one of the few female lords in Japan.

The family crest of the Iwamura Clan, called Maru-ni-Futatsubiki or Two horizonal lines inside a Circle

The portrait of Nobunaga Oda, attributed to Soshu Kano, owned by Chokoji Temple, in the late 16th century (licensed under Public Domain via Wikimedia Commons)

The situation became very serious for Otsuya when Shingen Takeda decided to fight against Nobunaga. This was because her territory was the buffer zone between Shingen and Nobunaga, which both clans wanted to own. Shingen sent his retainer, Torashige Akiyama with troops to capture Iwamura Castle in 1572. The castle was surrounded by the troops, but it survived for a while because it had very good defensive structures. Torashige negotiated an arranged marriage with Otsuya in order to be a part of the Takeda Clan. Otsuya accepted it.

The portrait of Shingen Takeda, owned by Jimyo-in Temple (licensed under Public Domain via Wikimedia Commons)

The portrait of Torashige Akiyama, attributed to Fuko Matsumoto, owned by Erinji Temple *(licensed under Public Domain via Wikimedia Commons)*

However, Nobunaga was very angry to hear about this. Nobunaga decided to send his troops to Iwamura Castle in 1575 after Shingen had died and the power of the Takeda Clan began to decline especially by the defeat in the battle of Nagashino Castle. The castle was besieged again but survived for 5 months because of its own strength. The attackers negotiated that the defenders could be saved if they surrendered. Torashige and Otsuya accepted this, however, the promise was a lie, so they were executed, which became a big tragedy during the Sengoku Period.

The illustration of Iwamura Castle, one of the Shoho Castle Illustrations, *exhibited by the National Archives of Japan*

Matsudaira Clan modernizes Castle

After that, several different lords governed the castle. In 1601 after the Tokugawa Shogunate was established, Ienori Matsudaira became the lord of the castle and the founder of the Iwamura Domain. Before his entry, the castle was probably a large and simple mountain castle with its buildings like the Main Hall at a high place. However, Ienori moved the Main Hall to the foot of the mountain to make it more convenient for him. He also modernized the mountain part by building stone walls which surrounded the enclosures. For example, the Main Enclosure on the top had two two-level turrets on the stone walls and two gates, but was empty inside during the late Edo Period. It might have been designed for emergencies like battles. In addition, Ienori also developed the castle town, which still has a good atmosphere to visit now.

The restored gate and turret of the Main Hall at the foot (taken by HiC from photoAC)

The Main Enclosure part of the illustration above

The former castle town of Iwamura (taken by rupann7777777 from photoAC)

To be continued in “Iwamura Castle Part2”

147.Takatenjin Castle Part1

The critical point between the Takeda and Tokugawa Clans

Location and History

Mountain being meant for Castles

Takatenjin Castle was located in Totomi Province which is the modern day the western part of Shizuoka Prefecture. It was a simple mountain castle made of soil, but it had a very good location for controlling the province. Many warlords wanted to capture this castle, as a result, what happened in the castle ultimately decided the destinies of both the Takeda Clan and Tokugawa Clan. The mountain where the castle was built on is only 132m high, about 100m from the foot. However, the ridges of it are complicatedly curved and its slopes are quite steep. Moreover, the top of it is not so large, and the view from the top is very clear. That means small defenders could easily protect this castle from attacks of large troops. This mountain was meant for castles.

The range of Totomi Province and the location of the castle

The relief map around the castle

The imaginary drawing of Takatenjin Castle, from the signboard at the site

Battles between Imagawa, Takeda and Tokugawa Clans

It is uncertain when the castle was first built, but the Imagawa Clan was the latest owner of the castle in the first 16th Century. After the Imagawa Clan’s power weakened, Ieyasu Tokugawa managed to capture the castle. Shingen Takeda, who was one of the greatest warlords, also wanted this castle, therefore attacked the castle in 1571. however, he failed to do so before his death in 1572. Singen’s son, Katsuyori Takeda tried to achieve this by building Suwahara Castle in 1573, the north region of Takatenjin Castle, as a foothold. Katsuyori assaulted Takatenjin Castle in 1574, then he managed to capture the castle because the defenders surrendered. He was probably at peak of his power having the largest territory and the highest reputation for the clan at that point.

The Portrait of Ieyasu Tokugawa, attributed to Tanyu Kano, owned by Osaka Castle Museum (licensed under Public Domain via Wikimedia Commons)

The Portrait of Katsuyori Takeda, owned by Koyasan Jimyoin, in the late 16th century (licensed under Public Domain via Wikimedia Commons)

However, the trend quickly changed after Katsuyori was completely defeated in the Battle of Nagashino near Nagashino Castle by the allies of Nobunaga Oda and Ieyasu in 1575. Ieyasu then started to counterattack in order to get the territory in Totomi Province which included Takatenjin Castle one by one. He first took Suwahara Castle away from Katsuyori in 1576. The castle had been the foundation of capturing Takatenjin Castle once for Katsuyori, but became the one for Ieyasu later on. Ieyasu next built a new castle called it Yokosuka Castle, in the west of Takatenjin Castle, in 1578 to supply his troops and avoid Takeda’s effort to supply to Takatenjin. On the other hand, Takeda improved Takatenjin Castle by building earthen walls, dry moats and ditches between enclosures in the western part of the castle. This was the only the part connected to other mountains. As a result, the castle became much stronger. The final battle was on the horizon.

Part of “Battle of Nagashino”folding screens, owned by Tokugawa Art Museum (licensed under Public Domain via Wikimedia Commons)

Ieyasu’s careful attack

Unlike Katsuyori, Ieyasu didn’t assault the castle. He probably understood he couldn’t get the castle so easily. He took a long time building many other fortresses around the castle to besiege it. The Six Takatenjin Forts (Fort Ogasayama, Nogasaka, Higamine, Shishigahana, Nakamura, and Mitsuiyama) are well known, but in fact, there were as many as 20 fortresses built. Each fortress had a distinct role, such as supplying like Fort Nakamura or preventing from Takeda’s attack like Fort Higamine, and containing the castle like Fort Sannosan. Therefore, Takatenjin Castle was completely isolated.

The location of Takatenjin Castle, Six Takatenjin Forts and Yokosuka Castle

Ieyasu’s long-awaited attack of Takatenjin Castle started in 1580, while Katuyori had problems sending his reinforcement to the castle. This was because Katsuyori’s strength decreased and had to prepare for many other enemies. The starving defenders of the castle urged Ieyasu to surrender. However, the leader of the allies, Nobunaga couldn’t accept it, which was a rare case even during the Sengoku Period when many battles happened. In 1581, the defenders made one last desperate attack from the castle and but were eventually defeated before the castle fell in the end.

Turning point of destinies of Ieyasu and Katsuyori

It was said that Nobunaga aimed to ruin Katsuyori’s reputation by showing that Katsuyori couldn’t protect the castle until the last moment. As a matter of fact, when Nobunaga invaded Katsuyori’s territory the next year, almost all retainers of Katsuyori surrendered or escaped from their master without fighting any battles. The battle of Takatenjin Castle would eventually lead to the destruction of the Takeda Clan which may have been a trigger for Ieyasu to be the final ruler of Japan later on.

A distant view of the ruins of Takatenjin Castle

To be continued in “Takatenjin Castle Part2”