Today, the ruins of Kanayama Castle have been well developed by Ota City. The mountain, where the ruins were located, are covered by several hiking courses including the routes to the ruins, where you can see many people enjoying and relaxing on them. For history fans visiting the ruins, it may be better to climb Nishiyama (the Western Mountain) course from such as Historic Site Kanayama Castle Guidance Facility.
The map around the castle
Drivers can also go straight to the parking lot on the mountain through the Kanayama Drive Way, about 700m away from the top, around Nishijo or the Western Castle area. The Western Mountain hiking course also meets the area, so a tour to the ruins usually starts there.
Defense system to prevent enemies from attacking Castle easily
To go to the center of the ruins, you need to go on the original or recently developed route towards the east. You will find several ditches which were built for preventing enemies from attacking the castle easily.
In particular, the one in front of the Lookout Tower was built by digging bedrock deeply, which looks very impressive. In addition, double entrances behind the ditch are surrounded by restored stone walls, and you can enter them after going across the earthen bridge over the ditch.
The tower above the entrance was rebuilt as an observation platform, where you can see great views of the city area and mountains around. This area must have been a pivot point of the castle.
Restored Main Entrance with Stone Walls and Paving
Next comes the main portion of the castle, called Mijo, which is divided by the Large Ditch, the largest one in the castle, and a small reservoir being covered with stone mounds, called Tsuki-no-ike or the Moon Pond.
The map of the main portion of the castle
Over the pond, you will see the outstanding Main Entrance in a valley, which are surrounded by great several tiered stone walls on both sides. The entrance also has stone paving with drainage ditches, so it looks like a European castle. These stone walls were recently restored by the officials based on the achievements of the excavations and studies, partially using the original stones.
They were thought to be completed by the Hojo Clan, the final owner of the castle. This is because they were piled in a method called Agodome style (in which all the stones in the bottom row are layered heavily to prevent the walls from collapsing) which the clan used in Hachioji Castle, their other branch castle. However, the excavation team also found that the stone walls were improved many times, so other clans might have started to build them.
An important and strong castle in the northern Kanto Region
Location and History
Yoshisada Nitta comes from Nitta Manor
Kanayama Castle was located on Kanayama Mountain in modern day Ota City, Gunma Prefecture. The area around the city was called Nitta Manor in the Middle Ages, where the Nitta Clan, a relative of the Minamoto Clan which originated from the Imperial Family, settled in. It was on Tozando Route, a major one in Kanto Region, and was sandwiched between Tone River and Watarase River, two major ones in the region as well. In the past, large rivers could provide rich farmland, water transportation, and even barriers when a battle happened. That’s why the area of Nitta Manor was considered important.
The range of Ota City and the location of the castle
Iezumi Iwamatsu builds Castle
Yoshisada Nitta is the most famous person of the clan, who attacked and defeated the Kamakura Shogunate in 1333. However, he was unfortunately defeated in 1338 by troops of the Ashikaga Shogunate which Takauji Ashikaga who was also a descendant of the Minamoto Clan established. After that, the Iwamatsu Clan, a branch of the Nitta but supporting the shogunate, followed the manor. The lord of the clan originally lived in the hall on a plain area, called the Iwamatsu Hall. However, it got too dangerous to continue to do so, because many battles happened all over the Kanto Region since the Kyotoku War started back in 1454. Therefore, the lord of the clan at that time, Iezumi Iwamatsu decided to build his new home base on Kanayama Mountain in the northern part of the manor, which would eventually be completed in 1469, and be called Kanayama Castle.
Yura Clan overthrows Iwamatsu Clan
In the Sengoku Period when the Kanayama Castle was active, a popular trend called Gekokujo or Overthrowing their lords was often seen. In the case of the Iwamatsu Clan, their senior vassal, the Yokose Clan overthrew the Iwamatsu Clan, by supporting a puppet lord and killing an unmanageable lord. For example, the lord, Naozumi Iwamatsu was forced to retire and devote all of himself to the field of linked poem called Renga. The Yokose Clan finally changed their family name to the Yura Clan, declaring they were actually another branch of the Nitta Clan, which also meant a descendant of the Minamoto Clan. They needed not only real power but also the authority the people could respect, to survive as a local warlord during the period.
Hojo Clan takes over and completes Castle
In the late 16th Century, much larger warlords than the Yura Clan, such as the Hojo, Uesugi, and Takeda Clans, battled each other over the Kanto Region. The policy of the Yura Clan was to deal and follow the strongest warlord each time as other local lords did. The lord of the clan, Narishige Yura even mediated between the Hojo Clan and Uesugi Clan in 1569 to provide Kanayama Castle for their negotiation, but unfortunately, the alliance lasted only a short time. The clan following one great warlord meant that they could be attacked by other great warlords. Kanayama Castle was actually attacked several times by all the three warlords, the Hojo, Uesugi, and the Takeda, however, never failed. That’s why this castle was considered impregnable and called one of the Seven Great Castles in the Kanto Region. The Kanto Region eventually belonged to the Hojo Clan, which forced the Yura Clan to hand Kanayama Castle over to the Hojo Clan in 1585.
The first stage of Kanayama Castle seemed to be built on around the top of the mountain and made of soil. As time passed by, the castle was developed and improved greatly. It is said that the Hojo Clan completed the final version of the castle. They expanded the range of the castle from the top to the western and southern ridges of the mountain. They also improved the main portion of the castle by building stone walls and even stone paving. The castle didn’t have the Main Tower which major castles in western Japan often had, but it is very rare case for those in eastern Japan to have full-scale stone walls at that time.
Abrupt ending of Castle
The main history of Kanayama Castle ended all too soon in 1590 when the ruler, Hideyoshi Toyotomi invaded the Hojo’s territory in order to unify Japan. Kanayama Castle was governed by the Hojo’s retainers, but many of them were ordered to gather in Odawara Castle, the Hojo’s home base, so only a few defenders remained in Kanayama Castle. That’s why they had to surrender and open it when they were attacked by the invasion troops led by Toshiie Maeda. After that, the castle was eventually abandoned.
The final place of the Otate Rebellion and Kagetora Uesugi
Location and History
Branch of Kasugayama Castle
Samegao Castle was located on a mountain in the western part of Echigo Province which is now Nigata Prefecture. It is uncertain when the castle was first built, but in the late 16th Century, it was one of the satellite castles of Kasugayama Castle, the home base of Kenshin Uesugi. Kenshin was one of the greatest warlords at that time in Japan, who built the network of castles to protect his home base. Samegao Castle is, in fact, rather well-known as the final battlefield of the Otate Rebellion and the place of Kagetora Uesugi’s death, who was defeated in the rebellion.
The location of the castle
Kagetora is adopted from Hojo to Uesugi
Kagetora Uesugi was an adopted child of Kenshin, but had been born as a family member of the Hojo Clan, which fought with Kenshin over the Kanto Region. The reason why Kagetora came to Uesugi was that Uesugi and the Hojo made peace temporarily in 1569 against the Takeda Clan. The Takeda clan broke the alliance of the three clans (Takeda, Imagawa and Hojo) by invading Imagawa territory. The Hojo clan was very angry about it. However, the new alliance between Uesugi and the Hojo lasted for only two years because the Hojo quit and reforged the alliance with the Takeda in 1571. Ordinarily, Kagetora could have been returned to the Hojo, but Kenshin let Kagetora stay as a part of the Uesugi clan for some reason. It is said that Kenshin personally liked Kagetora. Even though no portraits of Kagetora remain, records say he was attractive and looked beautiful.
Two adopted sons are against each other after Kenshin’s death
With the cessation of the alliance with the Hojo, Kenshin adopted another son from his relatives, called Kagekatsu Uesugi. Kenshin seemed to hope that Kagetora would support Kagekatsu and they would cooperate with each other. Many historians also say Kenshin had not clearly decided his successor before his sudden death in March 1578. In fact, these two adopted sons lived in the same Kasugayama Castle as if Kagekatsu was the master for a while after their father’s death. However, the situation didn’t allow them to make peace. The trusted vassals of Kagekatsu, who were the core members of the government, supported him. Other local lords in Echigo Province and some warlords outside the province supported Kagetora because he had come from the outside. Kagetora’s parents’ home, the Hojo and its ally, the Takeda especially wanted him to be the successor. That made the two successor candidates battle each other starting in May 1578, which was called the Otate Rebellion.
Otate or the Palace, was originally the residence for Norimasa Uesugi, who was a former shogunate deputy for the Kanto Region and Kenshin’s foster father. Kagetora escaped from Kasugayama Castle to the residence, about 5km from the castle. It became his home base during the battle for nearly one year. At the beginning of the battle, Kagetora was superior in terms of support to Kagekatsu until the lord of the Takeda, Katsuyori Takeda came to Echigo Province with his troops to support Kagetora in June. However, Kagekatsu let Katsuyori return to his home by giving a lot of money and promising to cede some territories. After that, the situation reversed as Kagekatsu had many native loyal retainers while Kagetora had few because of his career. Kagekatsu finally made a full-scale attack on the Otate Residence before it fell in March 1579. Kagetora escaped and tried to get to Odawara, his parental familial home base, Odawara Castle. He stopped by a castle of his supporter, Munechika Horie, which would be the place of his death. This place was called Samegao Castle.
Kagetora dies in Samegao Castle
Samegao Castle was a satellite castle, but had a large scale because it was on the way to Shinao Province (now Nagano Pref.), south of Echigo, where Kenshin and Shingen Takeda, who was Katsuyori’s father, often battled each other. It was a typical mountain castle at that time, using natural terrain to make it defensive. Many enclosures made of soil were built on the ridges. They were divided by artificial ditches and connected by narrow paths cut vertically on both sides. The routes through the valleys were zigzagged so that enemies could not attack the castle easily.
Even staying in the strong castle, Kagetora was not able to survive without reinforcement from the outside. He was attacked by Kagekatsu’s pursuing troops right away. Some records say Munechika Horie, the lord of the castle also betrayed Kagetora. Kagetora finally committed Harakiri (ritual suicide) at the age of 26 after the castle buildings were burned by the troops.