A Thorough Explanation of Miyazaki Castle’s History and Remains | From the Nanboku-cho Period to the Forty-Eight Castles of Ito
What is Miyazaki Castle?
Miyazaki Castle is a medieval mountain castle located on a hill approximately 90 meters above sea level, stretching from Ikenouchi-cho to Kamikita-kata in Miyazaki City, Miyazaki Prefecture. Also known as “Ikenouchi Castle,” “Mebiki Castle,” “Ryūhō Castle,” and “Masaku Castle,” it functioned as an important military base in Hyūga Province from the Nanboku-cho period to the Sengoku period.
The castle ruins retain remarkably well-preserved remains such as baileys, moats, and earthworks, making it a valuable historical site for understanding the structure of medieval mountain castles. It is counted as one of the Forty-Eight Castles of Ito and is an indispensable presence when discussing the history of medieval castles in Hyūga Province.
History of Miyazaki Castle
Construction during the Nanboku-cho Period and the Zushi Clan
The history of Miyazaki Castle begins during the turbulent Nanboku-cho period. The earliest recorded mentions of Miyazaki Castle can be found in the *Hyuga-ki* and *Tsuchimochi Monjo*, and it is believed to have been built in 1335 (Kenmu 2) or 1336 (Engen 1/Kenmu 3) by Zushi Rokuro Nyudo Suien and his son Jien (or possibly brothers), who belonged to the Southern Court.
The Zushi clan were powerful generals of the Southern Court and attempted to resist the Northern Court forces by constructing a castle in this area. However, shortly after its construction, the castle was attacked by Tsuchimochi Nobuei of the Northern Court, and it is said that the Zushi father and son were defeated and killed, and the castle fell. This battle was a symbolic event of the power struggle in Hyuga Province during the Nanboku-cho period.
The Tsuchimochi Clan’s Rule
The Tsuchimochi clan, who captured Miyazaki Castle, were powerful local lords who controlled the northern part of Hyuga Province. After the castle’s fall, Miyazaki Castle became the possession of the Tsuchimochi clan and was placed under their control. The Tsuchimochi clan, based in Nobeoka, was an important force that extended its influence throughout the northern part of Hyuga Province, and Miyazaki Castle is thought to have functioned as their southern base.
During the Tsuchimochi clan’s rule, Miyazaki Castle was maintained as a strategically important military stronghold for the Northern Court in Hyuga Province, playing a crucial role in conflicts with the Southern Court forces and other local lords.
The Ito Clan and the Forty-Eight Castles of Ito
In 1446 (Bun’an 4), Ito Suketaka, a powerful daimyo of Hyuga Province, captured Miyazaki Castle. This capture brought Miyazaki Castle under the control of the Ito clan, and it became one of the Forty-Eight Castles of Ito.
The Ito clan appointed their retainer, Ochiai Hikozaemon, as the castle lord of Miyazaki Castle, entrusting him with the maintenance and administration of the castle and the surrounding area. The Ito clan, based at Tonokori Castle, grew into a powerful daimyo (feudal lord) controlling most of Hyuga Province, and Miyazaki Castle functioned as an important branch castle within their sphere of influence.
The “Forty-Eight Castles of the Ito Clan” refers to a series of castles built by the Ito clan to control Hyuga Province. These castles were centered around Tonokori Castle, the Ito clan’s main castle, forming a network for governing their territory. Miyazaki Castle, in particular, served as the central castle in the Miyazaki region, responsible for regional administration and military defense.
Turmoil and Castle Abandonment in the Sengoku Period
In the late Sengoku period, the Ito clan declined due to conflicts with the Shimazu clan. Ito Yoshiyuki, defeated by Shimazu Yoshihiro at the Battle of Kizakihara in 1577, was driven out of Hyuga Province and fled to the Otomo clan in Bungo Province. With the downfall of the Ito clan, it is believed that many of the Forty-Eight Castles of the Ito Clan, including Miyazaki Castle, came under the control of the Shimazu clan.
After Toyotomi Hideyoshi’s conquest of Kyushu and the subsequent surrender of the Shimazu clan, the system of governance in Hyuga Province changed dramatically. During the Edo period, modern castles were constructed, and it is presumed that Miyazaki Castle, a medieval mountain castle, ceased to serve its military purpose and was abandoned.
Geography and Location of Miyazaki Castle
Topographical Characteristics
Miyazaki Castle is located in a hilly area stretching from Ikenouchi-cho to Kamikita-gata in Miyazaki City. It is a typical mountain castle utilizing the top of a hill approximately 90 meters above sea level, possessing a geographical advantage overlooking the surrounding plains.
The hill has a ridge extending north and south, and the castle was constructed by skillfully utilizing this natural terrain. Although relatively low in elevation for a mountain castle, its surrounding plains provided ample defensive advantages.
Military Importance
Miyazaki Castle’s location controlled a crucial transportation hub in Hyuga Province. Located on a hill overlooking the Miyazaki Plain, Miyazaki Castle allowed for early detection of enemy movements and functioned as a defensive base for the surrounding area.
From the Nanboku-cho period to the Sengoku period, Hyuga Province was the front line of conflict between the Southern and Northern Courts, or between the Ito and Shimazu clans. Miyazaki Castle was a crucial military stronghold in these conflicts and was repeatedly contested.
Current Location and Access
Currently, the Miyazaki Castle ruins remain on a hillside adjacent to a residential area in Ikenouchi-cho, Miyazaki City. It is relatively close to downtown Miyazaki and accessible by car. However, the castle ruins are in a forested area, so appropriate preparation is necessary for visiting.
Structure and Remains of Miyazaki Castle
Characteristics of the Layout
Miyazaki Castle has a typical layout (castle design and structure) of a medieval mountain castle. It utilizes the ridgeline of the hill to arrange multiple baileys (kuruwa), separated by moats (horikiri).
The castle features a central main enclosure (honmaru), with secondary enclosures arranged along the ridge. Each enclosure is reinforced with earthen ramparts. This structure is a clever design for gradually preventing enemy incursions and clearly demonstrates the defensive philosophy of medieval mountain castles.
Arrangement of Enclosures
Multiple enclosures have been identified at Miyazaki Castle. The main enclosure (honmaru), located at the highest point, is at the center, with secondary enclosures such as the second and third enclosures arranged in a stepped fashion.
Each enclosure is relatively flat, and while no building foundations have been found, it is presumed that residential facilities and warehouses were built there. The size of the enclosures indicates that there was sufficient space for the castle lord, his retainers, and soldiers to be stationed.
Moats and Earthen Ramparts
The moats and earthen ramparts are particularly noteworthy defensive features of Miyazaki Castle. The moats are dry moats dug to cut across the ridge, serving to physically prevent enemy incursions. Even today, clear traces of moats can be seen in multiple locations, and their large scale suggests a strong emphasis on defense.
Earthworks are earthen embankment-like structures built around baileys and important passages, functioning as defensive walls. The earthworks of Miyazaki Castle remain in good condition, and their height and width provide insight into the castle construction techniques of the time.
Presence of Stone Walls
As Miyazaki Castle is a medieval mountain castle, no full-fledged stone walls like those found in early modern castles have been confirmed. Defensive facilities mainly consist of earthworks and moats constructed through civil engineering, which is a typical characteristic of medieval mountain castles.
While there may be some traces of stone reinforcement in some areas, there are no masonry stone wall structures. This reflects the construction period and technological background, indicating that Miyazaki Castle belongs to the category of medieval mountain castles.
Preservation of Remains
The remains of Miyazaki Castle are preserved in remarkably good condition for a medieval mountain castle. Because it escaped development in the modern era, the basic structural elements such as baileys, moats, and earthworks remain clearly visible, allowing us to imagine its appearance at the time of its construction.
In particular, the depth of the moats and the height of the earthworks are still clearly discernible even after many years, making them valuable resources for the study of medieval castles. However, some areas are obscured by dense vegetation, requiring specialized knowledge to grasp the overall structure.
Position within the Ito Forty-Eight Castles
What are the Ito Forty-Eight Castles?
The Ito Forty-Eight Castles is a collective term for the group of castles built by the Ito clan, who ruled Hyuga Province during the Sengoku period, for the purpose of governing their territory. In reality, the number forty-eight is symbolic, and the actual number is said to have been either more or fewer.
These castles were located throughout Hyuga Province, centered around the Ito clan’s main castle, Tono-gun Castle, forming a network for governing the territory. Each castle was assigned a member of the Ito clan or a senior retainer as its lord, responsible for regional governance and defense.
The Role of Miyazaki Castle
Miyazaki Castle was the central fortress in the Miyazaki region among the 48 castles of the Ito clan. The fact that Ochiai Hikozaemon was appointed as the castle lord indicates the importance the Ito clan placed on this castle.
The Miyazaki region was located in the heart of Hyuga Province and was economically and militarily important. Miyazaki Castle functioned as the administrative center of this region and also served as one of the defensive lines against threats from the south.
Relationship with Other 48 Ito Castles
The 48 Ito castles cooperated with each other to defend their territories. Other Ito castles, such as Sadowara Castle and Takaoka Castle, were located around Miyazaki Castle, and by coordinating with these, a wide-area defense system was established.
It is believed that in emergencies, information was transmitted using smoke signals, and a system of mutual support among neighboring castles was in place. Miyazaki Castle, as part of this network, played a crucial role in supporting the Ito clan’s rule over their territory.
Current Status and Visiting Miyazaki Castle
Current Status of the Castle Ruins
Currently, the Miyazaki Castle ruins are a forest and not developed as a typical tourist destination. However, the remains are well-preserved, making it a valuable site for castle researchers and history enthusiasts.
Clear signage and facilities such as parking are limited, so prior research and preparation are necessary for a visit. Since you will be walking through a forest, appropriate clothing and equipment are required.
Points to Note When Visiting
When visiting the Miyazaki Castle ruins, please note the following: First, since it is a forest, long-sleeved shirts, long pants, and comfortable walking shoes are recommended. Insect repellent is also necessary during the summer months.
The remains are preserved as changes in topography such as earthworks and moats, so a basic understanding of medieval castles will deepen your understanding of them. If possible, it is recommended to consult books and materials related to castles beforehand.
Cultural Value
Miyazaki Castle Ruins are a valuable historical site where the remains of a medieval mountain castle are well-preserved. Its value as an important cultural heritage site that tells the history of Hyuga Province from the Nanboku-cho period to the Sengoku period is recognized.
It is also designated as a cultural property of Miyazaki City and is indispensable for understanding the region’s history. Appropriate preservation and utilization are expected in the future.
History of Miyazaki Castle and Hyuga Province
Hyuga Province during the Nanboku-cho Period
During the Nanboku-cho period, Hyuga Province was one of the regions where the Southern and Northern Courts fiercely fought. Forces belonging to the Southern Court, such as the Zushi clan, and forces belonging to the Northern Court, such as the Tsuchimochi clan, engaged in conflicts throughout the region.
The construction and fall of Miyazaki Castle symbolized the power struggles in Hyuga Province during this period. The history of the Southern Court’s temporary attempt to expand its power, only to be defeated by the Northern Court’s counterattack, mirrors the nationwide turmoil of the Nanboku-cho period.
The Ito and Shimazu Clans in the Sengoku Period
At the start of the Sengoku period (Warring States period), Hyuga Province became the battleground for the conflict between the two major powers: the Ito and Shimazu clans. At its peak, the Ito clan grew into a powerful daimyo controlling almost the entire province of Hyuga, but they were gradually pressured by the rise of the Shimazu clan.
The Battle of Kizakihara in 1577 (Tensho 5) was a decisive battle that sealed the Ito clan’s downfall. Ito Yoshiyuki, defeated in this battle, was driven out of Hyuga Province, and the 48 castles of the Ito clan came under Shimazu control. It is believed that Miyazaki Castle also ended its role within this historical context.
After Toyotomi Hideyoshi’s Conquest of Kyushu
Toyotomi Hideyoshi’s conquest of Kyushu drastically changed the system of governance in Hyuga Province. The Shimazu clan’s territory was reduced to Satsuma, Osumi, and parts of Hyuga, while much of Hyuga Province was distributed to other daimyo.
During the Edo period, Hyuga Province was divided and governed by various domains, including the Nobeoka, Takanabe, Sadowara, and Obi domains. During this time, modern castles were constructed, and Miyazaki Castle, a medieval mountain castle, completed its historical role and was abandoned.
Current Status and Challenges of Miyazaki Castle Research
Limitations of Documentary Sources
Documentary sources concerning Miyazaki Castle are limited, leaving challenges in unraveling its detailed history. While fragmentary descriptions can be found in texts such as the *Hyuga-ki* and *Tsuchimochi Monjo*, many aspects of its construction, structure, and the details of its successive lords remain unclear.
Future discoveries of new historical materials and re-examination of existing ones are expected to shed more light on the history of Miyazaki Castle.
The Need for Archaeological Investigation
No full-scale archaeological excavations have been conducted at the Miyazaki Castle site. While surveys and surface investigations of the remains have been carried out, many aspects of the buried remains and artifacts remain unexplained.
Archaeological excavations could reveal the layout of buildings, the ceramics and weapons used, potentially shedding light on aspects of the castle that are not known from written historical records.
Challenges of Preservation and Utilization
While Miyazaki Castle ruins retain well-preserved structures, development as a tourist destination has not progressed. As a valuable historical heritage site for the region, striking a balance between appropriate preservation and utilization is a challenge for the future.
It is desirable to provide more people with opportunities to learn about the history of Miyazaki Castle through the installation of information boards, the development of walking paths, and the creation of explanatory materials. At the same time, care must be taken to avoid damaging the preservation of the remains.
Summary
Miyazaki Castle is an important mountain castle that watched over the history of Hyuga Province from the Nanboku-cho period to the Sengoku period. Beginning with its construction by the Zushi clan, and continuing through the succession of the Tsuchimochi and Ito clans, it consistently functioned as a military and political center of the region.
The well-preserved remains, such as baileys, moats, and earthworks, are valuable resources for understanding the structure of medieval mountain castles. As one of the 48 castles of Ito, Miyazaki Castle played a crucial role in the castle network of Hyuga Province, and its historical significance cannot be overlooked.
As an important cultural heritage site of Miyazaki City, it is hoped that the Miyazaki Castle ruins will continue to be properly preserved and that its historical value will be widely recognized. Miyazaki Castle will continue to be an important site for understanding local history and for studying the history of medieval Japanese castles.
