A Thorough Explanation of the History and Remains of Yamaga Castle – Two Yamaga Castles in Higo and Chikuzen Provinces
The name “Yamaga Castle” refers to two different castles in Japanese history. One is the Yamaga Castle in Higo Province, located in Yamaga City, Kumamoto Prefecture, and the other is the Yamaga Castle in Chikuzen Province, located in Ashiya Town, Onga District, Fukuoka Prefecture. While both castles were residences of the Yamaga clan, who shared the same surname, their origins and historical backgrounds differ significantly. This article provides a detailed explanation of these two Yamaga Castles, including their history, structure, and current status.
Overview of Yamaga Castle in Higo Province
Location and Geographical Characteristics
Yamaga Castle in Higo Province was located in what is now Yamaga Onsen, Yamaga City, Kumamoto Prefecture. This castle was a hill castle (flatland castle) built on a low hill, strategically positioned overlooking the Yamaga Onsen hot spring resort area. The castle ruins are now home to temples and shrines such as Kiyotaki Shrine, Kosenji Temple, and Entonji Temple, preserving the appearance of the former castle.
It is also known by other names such as Yumachi Castle, Kamiichi Castle, and Kiyotaki Castle, and these names are thought to reflect the castle’s location and function. The name Yumachi Castle indicates its connection to Yamaga Onsen (hot springs), Kamiichi Castle reflects Yamaga’s character as a market town, and Kiyotaki Castle indicates its connection to Kiyotaki Shrine.
The Establishment and History of the Yamaga Clan
The Yamaga clan, who made Yamaga Castle in Higo Province their base, were a branch of the Kikuchi clan. It is believed that descendants of Saigo Taro Masataka, the second son of Kikuchi Noritaka (the ancestor of the Kikuchi clan), adopted the name Yamaga. The Kikuchi clan was a leading samurai family in Higo Province, and the Yamaga clan was established when a branch family of the Kikuchi clan established its base in Yamaga.
While there are no clear records of the castle’s construction period, it is estimated to have been built sometime between the late Kamakura period and the Nanboku-cho period. Records from 1351 (Shōhei 6) show that Prince Kaneyoshi, who had descended to Kyushu as the Seisei Shōgun (Commander-in-Chief of the Western Expedition), was at odds with the Yamaga clan, indicating that the Yamaga clan sided with the Northern Court during this period.
Yamaga Castle during the Nanboku-chō Period
During the Nanboku-chō period, Higo Province was the front line of fierce conflict between the Kikuchi clan (Southern Court) and the forces of the Northern Court. Unlike the main branch of the Kikuchi clan, the Yamaga clan sided with the Northern Court, leading to internal conflict within the family. This difference in political stance demonstrates the Yamaga clan’s uniqueness and indicates a high degree of regional independence.
Prince Kaneyoshi fought in various battles throughout Kyushu as a base for the Southern Court, but the Yamaga clan resisted him. It is believed that Yamaga Castle functioned as an important base for the Northern Court during this period.
The Sengoku Period and the Abandoned Castle
With the arrival of the Sengoku period, Higo Province became a situation where regional powers such as the Aso, Kikuchi, and Sagara clans vied for power. The Yamaga clan continued to maintain their power with Yamaga Castle as their base, but the latter half of the 16th century saw a turbulent period marked by events such as the Higo Provincial Uprising and the Shimazu clan’s northward advance.
After Toyotomi Hideyoshi’s Kyushu campaign in 1587, Sasa Narimasa entered Higo Province. However, following the Higo Provincial Uprising, Kato Kiyomasa became the lord of the northern half of Higo. During this process, Yamaga Castle was abandoned, bringing an end to its history as the Yamaga clan’s residence.
Current Status of Yamaga Castle Ruins
Currently, the Yamaga Castle ruins in Higo Province are incorporated into the urban area, and few clear remains exist. However, topographical features that suggest the castle’s former glory remain around Kiyotaki Shrine, allowing visitors to imagine its past.
The area around the castle ruins has developed into the Yamaga Onsen hot spring resort, a tourist destination lined with hot spring inns and shops. Traditional events such as the Yamaga Lantern Festival are held here, making it a region where history and culture are intertwined.
Overview of Yamaga Castle in Chikuzen Province
Location and Strategic Importance
Yamaga Castle in Chikuzen Province is a mountain castle built on a hill about 40 meters above sea level in Ashiya Town, Onga District, Fukuoka Prefecture. Located at the mouth of the Onga River, it was strategically important, controlling a key point for water transport. The Onga River is an important river flowing from the Chikuhō region to the Genkai Sea, and controlling its mouth meant controlling the distribution of goods and military movements.
The castle ruins are now maintained as Shiroyama Park, a place of relaxation for citizens. It is also known as a famous cherry blossom viewing spot, and is bustling with many visitors in spring.
Establishment of the Fujiwara-lineage Yamaga Clan
Yamaga Castle in Chikuzen Province was built by Fujiwara no Fujitsugu, who is said to be the younger brother of Fujiwara no Hidesato. The castle is believed to have been built during the Tenkei era (938-947), dating back to the mid-Heian period. Fujiwara no Hidesato is known as a warrior who suppressed the rebellion of Taira no Masakado, and his family spread throughout the country.
Fujiwara no Fujitsugu adopted the name Yamaga, and the castle became the residence of the Yamaga clan for generations. This Yamaga clan is a separate lineage from the Yamaga clan of Higo Province, and is a family descended from the Fujiwara clan. It is interesting that they share the same surname “Yamaga” but have different origins.
Castle Structure and Remains
Yamaga Castle in Chikuzen Province had a layout primarily oriented northwest and southeast. The main enclosure (honmaru) was located on the mountaintop and measured approximately 60 meters by 20 meters. The second enclosure (ninomaru) was located to the northwest and below, measuring approximately 70 meters by 30 meters.
The mountainside retains leveled areas believed to be lower baileys and outer baileys, exhibiting a typical structure of a medieval mountain castle. These baileys functioned as defensive structures, preventing enemy incursions.
Even today, these remains are relatively well-preserved within Shiroyama Park, allowing for an understanding of the castle’s structure in its heyday. From the main bailey, one can enjoy a panoramic view of the Onga River estuary and the Hibiki Sea, clearly demonstrating the castle’s function in monitoring water transport.
Late Heian Period to Kamakura Period
During the late Heian period, the time of Yamaga Tsunemasa and Hidetō, events related to the Tale of the Heike occurred. During the Genpei War, the samurai clans of Kyushu were divided between the Taira and Minamoto forces. The Yamaga clan was also caught up in this turmoil, playing an important role in the political movements in Kyushu, including their relationship with Dazaifu.
Entering the Kamakura period, the Yamaga clan served the shogunate as gokenin (vassals) and continued to maintain control of the Onga River estuary area. The economic benefits of water transport and the strategic importance of Yamaga Castle in northern Kyushu formed the base of its power.
The Sengoku Period and the Rule of the Aso Clan
With the onset of the Sengoku period, Chikuzen Province became a battleground for major powers such as the Ouchi, Otomo, Ryuzoji, and Shimazu clans. During this process, the Yamaga clan gradually lost power and came under the control of the Aso clan, lords of Hanaoka Castle.
The Aso clan were powerful local lords in Chikuzen Province, controlling the Onga district. It is believed that the Yamaga clan sought to survive the turmoil of the Sengoku period by becoming a subordinate of the Aso clan.
Toyotomi Hideyoshi’s Kyushu Campaign and the Abandonment of Castles
In 1587, Toyotomi Hideyoshi launched the Kyushu Campaign, forcing the Shimazu clan to surrender. During this process, medieval castles throughout Kyushu were abandoned, and Yamaga Castle in Chikuzen Province was no exception.
After conquering Kyushu, Hideyoshi implemented a policy of constructing modern castles throughout the region and abolishing smaller, medieval castles. Yamaga Castle was also abandoned as a result of this policy, bringing an end to its approximately 650-year history as a castle.
Current Site of Yamaga Castle in Chikuzen Province
Currently, the site of Yamaga Castle in Chikuzen Province has been developed into Shiroyama Park, a place of relaxation for local residents. Walking paths are maintained within the park, allowing visitors to view the remains of the main enclosure and the second enclosure.
Known as a famous cherry blossom viewing spot, it attracts many visitors in spring. From the observation deck, one can enjoy a panoramic view of the Onga River estuary, the townscape of Ashiya, and the Hibikinada Sea, allowing one to appreciate the strategic importance of the former castle.
Comparison of the Two Yamaga Castles
Background of Establishment
Yamaga Castle in Higo Province was built by a branch of the Kikuchi clan, a powerful samurai family in Kyushu. Yamaga Castle in Chikuzen Province was built by a branch of the Fujiwara clan who had descended from the Kanto region. Although they shared the same surname, “Yamaga,” their origins were completely different.
Such cases were not uncommon in medieval Japan; it was common to derive surnames from place names, so different families sometimes shared the same surname.
Differences in Location and Function
Yamaga Castle in Higo Province functioned as a base for controlling the Onsen-machi and Ichiba-machi areas, and was located at a key transportation hub in the inland region. On the other hand, Yamaga Castle in Chikuzen Province had a more maritime character, controlling the mouth of the Onga River, a key water transport point.
This difference in location reflects the difference in the strategic roles of each castle. Yamaga Castle in Higo Province functioned as a base for regional control, while Yamaga Castle in Chikuzen Province functioned as a monitoring base for water transport and maritime traffic.
Historical Development
Both castles played important roles from the Nanboku-cho period to the Sengoku period, but their political positions differed. Yamaga Castle in Higo Province belonged to the Northern Court during the Nanboku-cho period, while Yamaga Castle in Chikuzen Province was involved in the political developments of Kyushu from the late Heian period to the Kamakura period.
However, both castles were ultimately abandoned around 1587, ending their history at the same historical turning point: Toyotomi Hideyoshi’s conquest of Kyushu.
Historical Heritage of Yamaga Castle and Surrounding Areas
Historical Heritage of Yamaga City, Higo Province
Besides Yamaga Castle, Yamaga City has other important historical heritage sites. Of particular note is Kikuchi Castle. Kikuchi Castle is an ancient mountain castle built in the late 7th century, one of the Korean-style mountain castles constructed by the Yamato court for the defense of Kyushu.
Currently, the Kikuchi Castle ruins are maintained as a historical park, where visitors can see reconstructed buildings such as the drum tower and rice storehouse. There is also a museum called Onko Soseikan where you can learn about the history of ancient Kyushu. Furthermore, at the “Kuri to Sora” cafe, you can enjoy sweets made with Yamaga chestnuts, making it a tourist destination where history and modernity blend together.
In addition, Yamaga City has the remains of medieval castles such as Kumabe-kan and Shiromura Castle, demonstrating the depth of its history from the medieval to the early modern period.
History of the area around Ashiya Town, Chikuzen Province
The area around Ashiya Town flourished from ancient times as a key point for maritime transportation. As a point where the water transport of the Onga River and the sea transport of the Hibikinada Sea intersected, it became a center for the collection and distribution of goods.
In the medieval period, in addition to Yamaga Castle, castles such as Hanaoka Castle were built nearby, serving as a base for the control of Onga County. In the early modern period, it became part of the Fukuoka Domain of the Kuroda clan, and Ashiya developed as a port town.
Even today, Ashiya Town retains old townscapes and temples and shrines, preserving traces of its history.
Current Status and Challenges of Yamaga Castle Research
Limitations of Historical Sources
Historical sources concerning Yamaga Castle are limited, and many aspects remain unclear, particularly regarding its construction period and detailed castle structure. Medieval regional castles, if they did not become the site of large-scale battles, are rarely recorded in historical documents, and Yamaga Castle is no exception.
Regarding Yamaga Castle in Higo Province, fragmentary information can be obtained from historical sources related to the Kikuchi clan and records from the Nanboku-cho period, but the specific structure and changes of the castle must be relied upon through archaeological investigations.
Regarding Yamaga Castle in Chikuzen Province, information can be obtained from descriptions related to the Tale of the Heike and historical sources related to the Aso clan, but many details remain unclear.
Importance of Archaeological Investigations
In order to learn more about both castles in the future, archaeological investigations are essential. In particular, Yamaga Castle in Higo Province is undergoing urbanization, limiting opportunities for excavation, but even partial investigations may yield important information.
Yamaga Castle in Chikuzen Province is preserved as a park, allowing for planned investigations. Layout surveys and measurements are expected to lead to a more detailed understanding of the castle’s structure.
Position in Regional History
Yamaga Castles are important historical sites for understanding the activities of medieval samurai groups in their respective regions. Yamaga Castle in Higo Province represents the expansion of the Kikuchi clan, while Yamaga Castle in Chikuzen Province is significant in regional history research as an example of the Fujiwara clan’s advance into Kyushu.
Further research on both castles is expected to lead to a deeper understanding of medieval Kyushu’s samurai society and castle history.
Access and Visiting Yamaga Castle
Access to Yamaga Castle Ruins in Higo Province
The Yamaga Castle Ruins in Higo Province are located in the Yamaga Onsen hot spring resort area, in the heart of Yamaga City, Kumamoto Prefecture. From JR Kumamoto Station, take a Sanko Bus for approximately one hour, get off at Yamaga Bus Center, and then walk for about 10 minutes to reach the castle ruins.
By car, it’s about 20 minutes from the Ueki Interchange on the Kyushu Expressway. There are several parking lots around the castle ruins, making it easy to combine a visit with a stroll through the hot spring town.
The castle ruins are located within the grounds of temples and shrines such as Kiyotaki Shrine and Kosenji Temple, so you can combine a visit with a prayer. While there are few clearly visible remains, the topography allows you to imagine the castle’s appearance in its heyday.
Access to Yamaga Castle Ruins in Chikuzen Province
Yamaga Castle Ruins (Shiroyama Park) in Chikuzen Province is located in Ashiya Town, Onga District, Fukuoka Prefecture. It’s about 30 minutes by bus from JR Orio Station, or about 20 minutes by bus from JR Ebitsu Station, and a short walk from the Ashiya Town Bus “Shiroyama Park-mae” stop.
By car, it’s about 20 minutes from the Kurosaki Interchange on the Kitakyushu Urban Expressway, or about 30 minutes from the Wakamiya Interchange on the Kyushu Expressway. Parking is available at the park.
Shiroyama Park has well-maintained walking paths, allowing you to view the remains of the main enclosure and the second enclosure. From the observation deck, you can enjoy views of the Onga River estuary and the Hibikinada Sea, truly appreciating the importance of the castle’s location.
Summary
The two castles known as Yamaga Castle, each with its own distinct history and characteristics, are important historical sites for understanding the samurai society of medieval Kyushu. Yamaga Castle in Higo Province served as a base for a branch of the Kikuchi clan, while Yamaga Castle in Chikuzen Province was a base for a Fujiwara-affiliated samurai group, each playing a crucial role in their respective regions.
Both castles were abandoned during the Tensho period and are now cherished by the local community as temples, shrines, and parks. While clear remains are limited, the topography and historical documents allow us to imagine what they were like in their heyday.
Further research and investigations are expected to reveal more about these castles. Those interested in history should definitely visit the sites and experience the atmosphere of medieval castles firsthand.
