Anjo Castle Complete Guide: The Roots of Tokugawa Ieyasu and the Crucial Base of the Matsudaira Clan’s Development in Mikawa
What is Anjo Castle?
Anjo Castle (Anjo-jo, Ansho-jo) was a medieval hilltop castle located in Anjo-cho, Anjo City, Aichi Prefecture. Built in the heart of Hekikai District, Mikawa Province, this castle played an extremely important role in the development of the Matsudaira clan, which produced Tokugawa Ieyasu. Currently, it is maintained as Anjo Castle Ruins Park and is a designated historical site of Anjo City. The Anjo City History Museum and Anjo City Citizens’ Gallery have been built on the site, functioning as a center of local history and culture.
Anjo Castle, also known as “Mori Castle” and “Anjo Castle,” was a political and military stronghold in the Mikawa region during the Sengoku period, and the stage for fierce battles between the Oda and Matsudaira clans. The battles surrounding this castle had a significant impact on the fate of Tokugawa Ieyasu.
History of Ansho Castle
Construction and the Wada Clan Era
There are various theories regarding the construction period of Ansho Castle, but the most widely accepted theory is that it was built by Wada Chikahira during the Eikyo era (1429-1440). The Wada clan were shogunate land stewards who controlled the area around Hekikai District in Mikawa Province, and they developed Ansho Castle as a base for governing this region.
It is believed that the original Ansho Castle was closer to a residence than a full-fledged castle as it is today. However, with the arrival of the Sengoku period (Warring States period), its defensive functions were gradually strengthened.
Capture and Development by the Matsudaira Clan
Around 1471 (Bunmei 3), Matsudaira Nobumitsu, the lord of Iwatsu Castle in Mikawa Province, seized Ansho Castle through a stratagem. This event marked a crucial turning point in the Matsudaira clan’s expansion of power in the Mikawa region. Matsudaira Nobumitsu was the great-great-grandfather of Tokugawa Ieyasu, and the acquisition of Ansho Castle laid the foundation for the Matsudaira clan’s remarkable development. The Matsudaira clan, with Anjō Castle as their base, strengthened their influence over the surrounding region. In particular, during the time of Matsudaira Kiyoyasu, the Matsudaira clan made significant progress toward unifying Mikawa Province. Matsudaira Kiyoyasu was the grandfather of Tokugawa Ieyasu, and upon inheriting the family headship at a young age, he actively pursued military campaigns.
Matsudaira Kiyoyasu and the Relocation to Okazaki Castle
In 1524 (Daiei 4), Matsudaira Kiyoyasu captured Okazaki Castle and moved his base from Anjō Castle to Okazaki Castle. This relocation further expanded the Matsudaira clan’s sphere of influence, successfully strengthening their control over Mikawa. Even after the move to Okazaki Castle, Anjō Castle continued to function as an important branch castle of the Matsudaira clan, managed by a castle governor.
The Moriyama Incident and the Weakening of the Matsudaira Clan
In 1535 (Tenbun 4), Matsudaira Kiyoyasu was assassinated by his retainer, Abe Masatoyo, during an expedition to Owari Province. This incident is known as the “Moriyama Collapse.” Having lost their leader, the Matsudaira clan rapidly weakened, losing significant influence in Mikawa Province.
Taking advantage of this chaos, Oda Nobuhide (father of Oda Nobunaga) of Owari Province launched an invasion of Mikawa. Oda Nobuhide’s strategy, exploiting the Matsudaira clan’s weakening after the Moriyama Collapse, dramatically altered the fate of Anjo Castle.
Conquest by Oda Nobuhide
In 1540 (Tenbun 9), Oda Nobuhide successfully captured Anjo Castle. Nobuhide appointed his eldest son, Oda Nobuhiro, as the castle lord, making Anjo Castle a base for his Mikawa invasion. During this period, the Matsudaira clan sought survival by becoming a subordinate of the Imagawa clan, and Mikawa was the front line of the power struggle between the Oda and Imagawa clans.
Anjo Castle, under the command of Oda Nobuhiro, became a symbol of the Oda clan’s control over Mikawa and a top priority for the Matsudaira clan in recovering lost territory. ### Imagawa Yoshimoto’s Attack and the Capture of Oda Nobuhiro
In 1549 (Tenbun 18), the Imagawa army, acting on orders from Imagawa Yoshimoto, attacked Anjo Castle. After a fierce battle, Anjo Castle fell, and its commander, Oda Nobuhiro, was captured. This event would have a significant impact on the fate of Tokugawa Ieyasu (then known as Takechiyo).
At the time, the young Takechiyo (later Tokugawa Ieyasu) was in Owari as a hostage of the Oda clan. Imagawa Yoshimoto proposed an exchange of hostages for the captured Oda Nobuhiro and Takechiyo, which was realized. This exchange resulted in Takechiyo being moved to Suruga as a hostage of the Imagawa clan, marking a crucial turning point in Ieyasu’s childhood.
Changes After the Battle of Okehazama
After Imagawa Yoshimoto’s defeat by Oda Nobunaga at the Battle of Okehazama in 1560 (Eiroku 3), the situation in Mikawa changed dramatically. Matsudaira Motoyasu (later Tokugawa Ieyasu), who had been a hostage of the Imagawa clan, achieved independence and returned to Okazaki Castle. Subsequently, Motoyasu formed the Kiyosu Alliance with Oda Nobunaga, deepening his conflict with the Imagawa clan.
During this period, Anjo Castle lost its value as a frontline base and gradually declined in importance. For the Matsudaira clan (later the Tokugawa clan), whose base was Okazaki Castle, Anjo Castle became a rear-area subsidiary castle.
Towards Abandonment
With the end of the Sengoku period, Anjo Castle ceased to function as a military base and was abandoned. The exact date of its abandonment is unclear, but it is believed to have lost its function as a castle after Tokugawa Ieyasu was transferred to the Kanto region, or even before.
Structure and Layout of Anjo Castle
Location as a Hilltop Castle
Anjo Castle is classified as a hilltop castle. It was built on a slightly elevated terrain rather than completely flat land, and was situated in a location that offered a panoramic view of the surrounding area. This location offered defensive advantages and also held a strategic position as the center of Hekikai District in Mikawa Province, controlling a crucial transportation hub.
Castle Size and Structure
The exact size and structure of Ansho Castle are not fully understood due to the limited number of surviving remains. However, based on archaeological excavations and historical documents, the following characteristics have been inferred:
It is believed that, like a medieval castle, defensive facilities centered on earthworks and moats were arranged. It lacked features of early modern castles such as stone walls and keeps, suggesting a practical structure for warfare during the Sengoku period. Multiple baileys (kuruwa) were likely arranged around the main bailey, each demarcated by earthworks and moats.
Current Remains
Currently, very few remains of Ansho Castle exist. The castle site has been developed as Ansho Castle Ruins Park, and the remaining traces of earthworks and the topographical undulations allow visitors to imagine the castle’s former appearance. Information boards are installed within the park, allowing visitors to learn about the castle’s history and structure.
Current Remains The Anjo City History Museum displays materials and excavated artifacts related to Ansho Castle, allowing visitors to gain insight into the castle’s true nature. Excavations have uncovered ceramics and fragments of weapons, providing insights into the life and battles of the time.
Highlights of Ansho Castle
Ansho Castle Ruins Park
The Ansho Castle ruins are now maintained as Ansho Castle Ruins Park, a place of relaxation for citizens. Walking paths are maintained within the park, allowing visitors to enjoy the changing seasons while strolling through history. During cherry blossom season, many visitors come to enjoy the blossoms, and the park is a beloved spot for locals.
Several information boards explaining the castle’s history are installed within the park, allowing visitors to learn in detail about the history of the Matsudaira clan and their battles with the Oda clan. The locations of former baileys and moats are also indicated, allowing visitors to imagine the castle’s layout while exploring.
Anjo City History Museum
The Anjo City History Museum, built on the site of Anjo Castle, is an essential facility for learning about the history of Anjo Castle and the Matsudaira clan. The permanent exhibition provides detailed information on the history of Anjo Castle, the development of the Matsudaira clan, and their relationship with Tokugawa Ieyasu.
The museum displays artifacts unearthed during archaeological excavations, as well as weapons and historical documents from the period, allowing visitors to gain a concrete understanding of Mikawa during the Sengoku period. A reconstructed model of Anjo Castle is also on display, providing a visual understanding of the castle’s overall structure.
Castle Site Monument and Information Board
A stone monument marking the “Anjo Castle Site” stands within the park, serving as a popular photo spot. Information boards detailing the castle’s history, the Matsudaira clan, and its relationship with Tokugawa Ieyasu are also installed, allowing visitors to deeply understand the castle’s importance and historical significance.
Traces of Earthworks
Slight traces of earthworks remain in some parts of the park. Although much has been lost due to modern construction, the topography allows us to imagine the layout of the defensive structures at the time. For history enthusiasts, even these few traces offer the pleasure of imagining the castle’s appearance in its heyday.
The Relationship Between Anjō Castle and Tokugawa Ieyasu
The Importance as the Root of the Matsudaira Clan
Anjō Castle is an extremely important castle when discussing the roots of Tokugawa Ieyasu. Matsudaira Nobumitsu, Ieyasu’s great-great-grandfather, acquired Anjō Castle, establishing the Matsudaira clan’s power base in Mikawa Province. Later, during the time of his grandfather, Matsudaira Kiyoyasu, they made significant progress toward unifying Mikawa, establishing their position as a Sengoku daimyo (feudal lord).
The period when Anjō Castle was the Matsudaira clan’s base was a crucial time in their growth from a minor local lord to a Sengoku daimyo. The experience and knowledge gained at this castle formed the foundation for the later development of the Tokugawa clan.
The Exchange of Takechiyo (Ieyasu) as Hostage
The fall of Anjo Castle and the capture of Oda Nobuhiro in 1549 drastically altered the fate of the young Takechiyo (Tokugawa Ieyasu). The exchange of hostages between Oda Nobuhiro and Takechiyo changed Ieyasu’s status from a hostage of the Oda clan to a hostage of the Imagawa clan.
Without this event, Ieyasu may have grown up under the influence of the Oda clan and led a completely different life. His experience as a hostage of the Imagawa clan in Suruga is believed to have greatly influenced the formation of his character and the acquisition of his political skills.
A Place Associated with Lord Ieyasu
Currently, Anjo City promotes itself as “Lord Ieyasu’s Hometown” for tourism, and the Anjo Castle ruins hold an important position as one of the places associated with him. As the castle where Ieyasu’s ancestors were based, it is a place visited by many history enthusiasts and tourists.
Access Information
Access by Public Transportation
Train and Bus
- Approximately 25 minutes on foot from JR Tokaido Main Line “Anjo Station”
- Approximately 15 minutes on foot from Meitetsu Nishio Line “Minami-Anjo Station”
- Take the “Ankuru Bus” (city loop bus) from Anjo Station and get off at the “Ansho Castle Ruins/History Museum” bus stop.
Meitetsu Train
- Transfer to the Meitetsu Nishio Line at Meitetsu Nagoya Main Line “Shin-Anjo Station” and get off at “Minami-Anjo Station”. Approximately 15 minutes on foot.
Access by Car
Expressway
- Approximately 30 minutes from Tomei Expressway “Okazaki IC”
- Approximately 20 minutes from Isewangan Expressway “Toyota Minami IC”
- Accessible from National Route 1 and National Route 23
Parking
- Anjo City History Museum Parking Lot (Free): Approximately 100 spaces
- Parking spaces are also available around Ansho Castle Ruins Park.
Address and Basic Information
- Address: 30 Shirobori, Anjo-cho, Anjo City, Aichi Prefecture (Anjo Castle Ruins Park)
- Anjo City History Museum: 30 Shirobori, Anjo-cho, Anjo City, Aichi Prefecture
- Free to visit (Park is open 24 hours)
- Admission Fee: Free (History Museum is charged)
Nearby Tourist Attractions
Honsho-ji Temple
Located about 10 minutes by car from Anjo Castle, Honsho-ji Temple was a base for the Mikawa Ikko-ikki rebellion. The remains of the castle temple are well-preserved, and you can see the earthworks and moats. It is an important historical site for understanding the relationship between Tokugawa Ieyasu and the Ikko-ikki.
Okazaki Castle
Okazaki Castle, where Matsudaira Kiyoyasu moved his base from Anjo Castle, is famous as the birthplace of Tokugawa Ieyasu. Located about 30 minutes by car from Anjo Castle, the castle tower has been restored. The Ieyasu Museum is also located on the premises, where you can learn about Ieyasu’s life in detail.
Matsudaira Village, the Family Temple of the Sakurai Matsudaira Clan
Matsudaira Village, considered the birthplace of the Matsudaira clan, is another spot worth visiting along with Anjo Castle. It contains Takatsuki-in Temple, which enshrines the founder of the Matsudaira clan, and Matsudaira Toshogu Shrine, allowing you to explore the roots of the Matsudaira clan.
Tourist Facilities in Anjo City
- Anjo Industrial Culture Park Denpark: A park where you can enjoy flowers throughout the four seasons.
- Anjo Tanabata Festival: One of the leading festivals in the Tokai region, held every August.
- Temples and Shrines in Anjo City: Historic temples and shrines are scattered throughout the city.
Points to Visit and Recommendations
Best Season for Visiting
Anjo Castle Ruins Park can be visited throughout the year, but the following times are particularly recommended.
Spring (Late March – Early April)
During the cherry blossom season, the park is adorned with beautiful cherry blossoms, allowing visitors to enjoy a historical stroll while admiring the blossoms. It’s a popular cherry blossom viewing spot among locals.
Autumn (November)
The autumn foliage is beautiful, and the pleasant weather makes it ideal for a stroll. Combined with a visit to the history museum, it’s a great time to spend leisurely time.
Estimated Time Required
- Park stroll only: 30 minutes – 1 hour
- Including a visit to the history museum: 2 – 3 hours
- Sightseeing including surrounding historical sites: Half a day – 1 day
Utilizing the History Museum
When visiting Anjo Castle, we highly recommend visiting the Anjo City History Museum. Through exhibits and models, you can learn in detail about the historical background, the castle’s structure, and the development of the Matsudaira clan, which are difficult to understand from the castle ruins alone.
The museum also regularly holds special exhibitions, allowing you to enjoy different themes depending on the time of your visit.
Photography Tips
- The stone monument at Ansho Castle Ruins is a classic spot for commemorative photos.
- The remnants of earthworks and the undulations of the terrain within the park.
- The exterior of the history museum (the contrast between modern architecture and historical sites).
- The scenery is especially beautiful during cherry blossom season.
Ansho Castle and Mikawa in the Sengoku Period
The Road to Mikawa Unification
Ansho Castle played a crucial role in the Matsudaira clan’s quest to unify Mikawa. From the late 15th century, when Matsudaira Nobumitsu acquired the castle, until the early 16th century, when Kiyoyasu moved to Okazaki Castle, it functioned as the Matsudaira clan’s base for approximately 50 years.
During this period, the Matsudaira clan expanded their power by subjugating surrounding local lords from Ansho Castle. Especially during the time of Matsudaira Kiyoyasu, they brought almost all of Mikawa under their control through aggressive military actions, establishing their position as a powerful Sengoku daimyo.
The Front Line of the Conflict Between the Oda and Imagawa Clans
In the mid-16th century, Mikawa became a buffer zone between the two major powers: the Oda clan of Owari and the Imagawa clan of Suruga. Anjo Castle was located on the front lines, becoming the focal point of the struggle between the two forces.
Oda Nobuhide’s capture of Anjo Castle strengthened the Oda clan’s influence in Mikawa, but Imagawa Yoshimoto’s counterattack brought it back under Imagawa control. This conflict lasted for about 10 years, forcing the local lords of Mikawa to engage in complex diplomacy between the Oda and Imagawa clans.
The Resurgence of the Matsudaira Clan and its Development into the Tokugawa Clan
After the Battle of Okehazama, Matsudaira Motoyasu (Tokugawa Ieyasu) declared independence from the Imagawa clan and formed an alliance with Oda Nobunaga. From this period, the Matsudaira clan rapidly recovered its power and achieved the unification of Mikawa.
Subsequently, Ieyasu expanded his power into Totomi and Suruga, eventually developing into the Tokugawa clan, who established the Edo Shogunate. At the heart of this development lay the governing abilities and military strength cultivated by the Matsudaira clan at Anjo Castle.
Summary: The Historical Significance of Anjo Castle
Anjo Castle played an extremely important role in the development of the Matsudaira clan, which produced Tokugawa Ieyasu. From its construction by the Wada clan, to its prosperity as the Matsudaira clan’s base, the struggles between the Oda and Imagawa clans, and finally its abandonment, its approximately 150-year history can be considered a microcosm of Mikawa during the Sengoku period.
Although very few remains of the castle exist today, its history is preserved for future generations through Anjo Castle Ruins Park and the Anjo City History Museum. Anjo Castle is an indispensable historical site on a journey to explore the roots of Tokugawa Ieyasu.
When visiting Aichi Prefecture, be sure to visit Anjo Castle, in addition to famous castles like Okazaki Castle and Nagoya Castle. While it lacks a large keep or stone walls, the footprints of the Matsudaira clan, who significantly shaped Japanese history, are undeniably etched there. A stroll through this quiet park, while reflecting on Mikawa during the Sengoku period, will be a valuable experience for history buffs.
