The History of Arato Castle
A Stronghold of the Yamada Clan
Arato Castle was originally built during Japan’s Warring States period as the residence of the Yamada clan, a branch of the powerful Murakami clan. It served as a subsidiary fortress of Katsurao Castle, the Murakami clan’s main stronghold, and occupied an important strategic position for controlling the surrounding area.
The castle’s location on a mountain made it particularly valuable as a defensive position. From its elevated setting, the surrounding valleys and routes could be monitored, making Arato Castle an important part of the regional network of medieval fortifications.
Takeda Shingen’s Advance into Shinano
In 1553, during Takeda Shingen’s invasion of Shinano, the political situation surrounding Arato Castle changed dramatically. Shingen’s retainer Sanada Yukitsuna, better known as Sanada Yukitaka, successfully persuaded the Yashiro clan, retainers of Murakami Yoshikiyo, to switch allegiance.
After Katsurao Castle fell, Yashiro Masakuni was rewarded by being allowed to move to Arato Castle. From there, he became a supporter of the Takeda side and used the castle as his base.
From the Takeda Clan to the Uesugi and Tokugawa
The political landscape changed once again in 1582, when the Takeda clan was destroyed. Yashiro Hidemasa initially came under the control of Oda Nobunaga, but following Nobunaga’s death, the Tenshō-Jingo War plunged Shinano into another period of conflict.
The Yashiro clan subsequently joined the forces of Uesugi Kagekatsu and became associated with the defense of Kaizu Castle, now known as Matsushiro Castle. However, Yashiro Hidemasa reportedly fell into conflict with the castle’s commander, Yamaura Kagekuni, and their relationship deteriorated.
In 1584, Hidemasa was suspected of secretly cooperating with the Tokugawa side and became an enemy of Uesugi Kagekatsu. He set fire to Arato Castle and escaped, later joining the Shiozaki clan. He subsequently took refuge at Sanoyama Castle, but after coming under attack from Uesugi forces, he fled toward Omi. The Uesugi army continued its pursuit and eventually captured Omi Castle, bringing the conflict to an end.
The Castle After the Warring States Period
Following these events, Arato Castle was abandoned and was never again used as a major fortress. Yashiro Hidemasa escaped to the Tokugawa domain and later served as a hatamoto, a direct retainer of the Tokugawa shogunate. His descendants continued to serve the Tokugawa government until the end of the Edo period.
There is also a tradition that part of the surrounding territory was later granted to Sanada Nobushige, better known as Sanada Yukimura, while he was being held as a hostage by Uesugi Kagekatsu.
Stories and Historical Episodes
The Deaths of Yamada Kunimasa and Azuma Kiyotsuna
Arato Castle is connected with several episodes from the fierce struggles of the Warring States period. In April 1551, Yamada Kunimasa, a member of the Murakami clan, and Azuma Kiyotsuna were killed at Toishi Castle following a conflict involving Yazawa Yoritsuna, the elder brother of Sanada Yukitaka. Their deaths became part of the complex power struggles between the Murakami and Sanada factions.
A Letter of Commendation from Takeda Harunobu
Another historical record describes a reward given to Terao Gyōbu-no-shōyū for successfully attacking and capturing a castle after the enemy stronghold had been moved to Yamada Castle. A letter of commendation from Takeda Harunobu, the future Takeda Shingen, is believed to date from around 1555.
Arato Castle Today
Reconstructed Features of a Medieval Mountain Fortress
The former castle site was once developed as a theme park, with attractions including a Ferris wheel and ropeway, as well as a memorial tower for people who died during the Manchurian settlement program. These facilities were later removed, and the area was redeveloped as Chikuma City Shiroyama Historic Park.
Although some of the original castle remains were damaged during earlier development, the present historic park recreates key elements of a medieval Japanese mountain castle. Visitors can see reconstructed castle entrances known as koguchi, wooden watchtowers, barracks, and the lord’s residence in the main fortified area.
The combination of mountain scenery and reconstructed defensive structures makes the site an excellent place to imagine what a Sengoku-period castle may have looked like. Walking through the grounds also offers a sense of how castles were designed to take advantage of steep terrain and natural defenses.
A Popular Location for Japanese Historical Dramas
Arato Castle has also attracted attention as a filming location for Japanese historical television dramas. In 2007, the NHK Taiga drama Fūrinkazan used the site to portray Uminokuchi Castle. In 2011, the Taiga drama Gō: Himetachi no Sengoku used Arato Castle as a setting representing Odani Castle.
For visitors familiar with Japanese historical dramas, the reconstructed fortress provides an opportunity to see a location that has been used to recreate the world of the Sengoku period on screen.
Memorial to the Victims of the Manchurian Settlement Program
In 1967, a memorial tower was erected at the site to commemorate people from the former Sarashina and Hanishina districts who died during the Manchurian settlement program before and after the end of World War II. The monument recorded that 649 of 800 people from these areas died within one week after the war ended.
As part of the redevelopment of the historic park, the memorial was moved in 1994 to a branch temple of Zenkoji Daihongan. The relocation reflects the changing role of the former castle site, from a place of wartime remembrance to a protected historic site centered on the medieval history of the region.
Experiencing Sengoku History in the Mountains
One of the greatest attractions of Arato Castle is the way its history is connected with the wider political struggles of medieval Shinano. The site was linked to the Murakami, Takeda, Oda, Uesugi, and Tokugawa factions, as well as to important figures such as Takeda Shingen, Sanada Yukitaka, and Yashiro Hidemasa.
Rather than being simply a collection of stone walls, Arato Castle represents a place where the ambitions of rival warlords repeatedly collided. Its elevated position also helps visitors understand why mountain castles played such an important role in the military geography of the Sengoku period.
Visiting Arato Castle
Arato Castle is located in Kamiyamada, Chikuma City, Nagano Prefecture. From the reconstructed fortifications, visitors can enjoy views of the surrounding mountains while exploring the remains and recreations of the medieval stronghold.
The site can be reached by taxi in approximately 10 minutes from Togura Station on the Shinano Railway. By car, it is approximately 20 minutes from the Sakaki Interchange on the Joshinetsu Expressway. Parking is available.
A Mountain Castle Where History Comes Alive
Arato Castle is a valuable historic site where the turbulent history of medieval Shinano can be experienced in a mountain setting. Its story encompasses the rise and fall of the Murakami and Takeda clans, the shifting alliances of the Uesugi and Tokugawa factions, and the dramatic conflicts that shaped the region during the Sengoku period.
Today, the carefully maintained historic park allows visitors to explore reconstructed castle gates, watchtowers, barracks, and other features while imagining the castle as it once stood. Combined with the surrounding mountain scenery, the site offers a distinctive way to discover the history of Chikuma and the wider story of samurai warfare in central Japan.
For travelers interested in Japanese castles, samurai history, and lesser-known cultural heritage sites, Arato Castle is a rewarding destination away from the major tourist centers. A visit provides not only a glimpse into a medieval mountain fortress, but also a deeper understanding of the people and rivalries that shaped the history of Shinano.