Matsushiro Castle Ruins are located in Matsushiro, Nagano City, Nagano Prefecture.
The castle was originally known as Kaizu Castle and served as an important military base for Takeda Shingen during the Battles of Kawanakajima.
After the early Edo period, the Sanada clan governed the Matsushiro Domain from this castle for approximately 250 years. The surrounding town developed into the political, cultural and economic center of the domain.
Today, the site is designated as a National Historic Site. Reconstructed gates, wooden bridges, stone walls, earthworks and moats allow visitors to imagine how the former castle was organized.
In this first part of our guide, we explore the history of Matsushiro Castle, its connection with Takeda Shingen and the Battles of Kawanakajima, and the development of the castle town under the Sanada clan.
What Is Matsushiro Castle?
Matsushiro Castle was a flatland castle built near the Chikuma River.
Unlike mountain castles constructed on steep peaks, it used the river, surrounding wetlands, moats and earthworks as part of its defensive system.
The main enclosure was surrounded by stone walls and moats. Additional enclosures and defensive entrances protected the castle and controlled movement into its central area.
| Present name | Matsushiro Castle Ruins |
|---|---|
| Former name | Kaizu Castle |
| Castle type | Flatland castle |
| Location | Matsushiro, Nagano City, Nagano Prefecture |
| Historic designation | National Historic Site |
| Principal historic associations | Takeda clan, Battles of Kawanakajima and Sanada clan |
Kaizu Castle and the Battles of Kawanakajima
The history of the castle is closely connected with the conflict between Takeda Shingen of Kai Province and Uesugi Kenshin of Echigo Province.
During the 16th century, the two powerful warlords competed for control of northern Shinano Province. Their military confrontations are collectively known as the Battles of Kawanakajima.
The Kawanakajima area was strategically important because roads and river routes connecting northern and central Shinano met there.
Controlling this region meant controlling the movement of soldiers, supplies and information.
A Strategic Base for the Takeda Clan
Kaizu Castle was established as an important base from which the Takeda clan could control northern Shinano and monitor the movements of the Uesugi forces.
The castle stood close to the Chikuma River and within reach of the Kawanakajima plain.
Its location allowed the Takeda army to secure transportation routes, gather military information and prepare for conflict.
Was the Castle Designed by Yamamoto Kansuke?
Kaizu Castle is often associated with Yamamoto Kansuke, a military strategist who served Takeda Shingen.
Local tradition and later historical accounts describe Kansuke as being involved in the castle’s design.
However, surviving historical evidence does not establish every detail of its construction with certainty.
It is therefore more accurate to understand the connection with Yamamoto Kansuke as an important tradition surrounding the castle rather than as a completely verified historical fact.
The Fourth Battle of Kawanakajima
The best-known confrontation between Takeda Shingen and Uesugi Kenshin took place in 1561.
This battle is generally known as the Fourth Battle of Kawanakajima.
According to traditional accounts, Uesugi forces descended from Mount Saijo and attacked the Takeda army on the plain.
The battle became one of the most famous episodes of Japan’s Warring States period and is often represented by the legendary direct confrontation between Shingen and Kenshin.
Kaizu Castle played an important role as a Takeda base during the campaign.
When visiting the castle ruins, it is helpful to consider not only the remaining structures but also the surrounding geography connecting the castle, the Chikuma River, Mount Saijo and the Kawanakajima plain.
From Kaizu Castle to Matsushiro Castle
After the fall of the Takeda clan, control of the castle changed several times as political power shifted across Japan.
The castle came under the influence of different rulers during the final years of the Warring States period and the beginning of the Edo period.
Its name also changed over time. The former name Kaizu Castle was eventually replaced by Matsushiro Castle.
The name “Matsushiro” became established during the Edo period and remains in use today.
The Arrival of the Sanada Clan
A major turning point came in 1622, when Sanada Nobuyuki entered Matsushiro.
Nobuyuki was the elder brother of Sanada Nobushige, commonly known as Sanada Yukimura.
While Nobushige became famous for fighting on the Toyotomi side during the Siege of Osaka, Nobuyuki survived the political changes of the period and established the foundation of the Sanada domain.
After moving to Matsushiro, the Sanada family governed the domain for ten generations until the end of the Edo period.
Sanada Nobuyuki and Matsushiro
Sanada Nobuyuki had already experienced the turbulent transition from the Warring States period to the Tokugawa government.
His arrival connected Matsushiro Castle with the history of one of Japan’s best-known samurai families.
Under the Sanada clan, Matsushiro developed from a military stronghold into the administrative center of a stable castle town.
A Domain of 100,000 Koku
The Matsushiro Domain was assessed at approximately 100,000 koku.
A koku was a traditional unit used to measure rice production and the economic strength of a domain.
The expression “Sanada 100,000-koku castle town” continues to represent Matsushiro’s identity today.
The castle was the political center of the domain, while samurai residences, temples, merchant districts and educational institutions developed around it.
Development of the Castle Town
Matsushiro Castle cannot be understood separately from the surrounding town.
The streets, waterways, temples and former samurai residences reflect the organization of an Edo-period castle town.
Areas near the castle were occupied by domain offices and high-ranking retainers. Merchants and craftspeople lived and worked in districts farther from the castle’s central enclosures.
Some of this historic town structure can still be recognized while walking through present-day Matsushiro.
Samurai Residences
Several former samurai residences remain around the castle town.
These buildings show how retainers of the Matsushiro Domain lived and how residential spaces, gardens and gates were arranged.
The Former Higuchi Family Residence is one of the accessible examples located within walking distance of the castle.
Temples and Cultural Heritage
Matsushiro contains numerous temples connected with the Sanada family and the retainers of the domain.
These religious sites preserve graves, memorials, architecture and historical traditions that cannot be seen within the castle grounds alone.
Exploring them reveals that Matsushiro was not only a military and political center but also a town shaped by religion and culture.
Education in the Matsushiro Domain
During the late Edo period, the Matsushiro Domain placed considerable importance on education.
The Bunbu School opened in 1855 and provided instruction in both academic and martial subjects.
Students studied literature and Confucian learning while also training in swordsmanship, archery and spear techniques.
The surviving school buildings make the Bunbu School one of the most important historic sites in Matsushiro.
Sakuma Shozan and the Late Edo Period
Matsushiro is also associated with Sakuma Shozan, an influential scholar of the late Edo period.
He studied Western science, military technology and international affairs at a time when Japan faced increasing pressure from foreign powers.
Shozan argued that Japan should combine Eastern ethics with Western scientific knowledge.
His activities demonstrate that Matsushiro was connected not only with samurai traditions but also with the intellectual and technological changes that preceded the Meiji Restoration.
The End of the Castle
After the abolition of Japan’s feudal domains in the early Meiji period, Matsushiro Castle lost its administrative role.
Buildings were removed or destroyed, and the former castle grounds were gradually transformed.
The original keep and many other structures no longer survive.
However, archaeological investigations have revealed the foundations, stone walls, moats and arrangement of important entrances.
Restoration of Matsushiro Castle Ruins
Preservation and restoration work has been carried out to help visitors understand the historic structure of the castle.
Gates, wooden bridges, stone walls and earthworks have been reconstructed or repaired using archaeological evidence and historical records.
The restored Taikomon Gate and Kita-Akazumon Gate are now among the principal landmarks of the site.
The aim is not to create a modern imitation of a castle, but to present the layout and appearance of the historic site as accurately as available evidence allows.
How to Explore the Castle Ruins
Begin by observing the castle from outside the moat.
This wider view makes it easier to understand the relationship between the gates, bridges, stone walls and surrounding defensive spaces.
After entering the inner bailey, walk slowly around the perimeter and look at the differences between the stone walls and earthworks.
- Observe the main entrance and its defensive layout
- Look closely at the natural stones used in the walls
- Walk around the inner bailey to understand its shape
- View the moat and wooden bridges from outside
- Consider the relationship between the castle and the Chikuma River
The castle grounds are relatively compact, but understanding their history and structure makes the visit far more rewarding.
Before Continuing to Part 2
Matsushiro Castle began as Kaizu Castle, a strategic base associated with Takeda Shingen and the Battles of Kawanakajima.
It later became the center of the Matsushiro Domain, governed by the Sanada clan for approximately 250 years.
The castle and surrounding town preserve different layers of history, from the Warring States period to the final years of the Edo period.
In Part 2, we look more closely at the reconstructed gates, stone walls, seasonal scenery, opening hours, access, parking and a recommended walking route through Matsushiro.