Inabayama Castle

Inabayama Castle
Alpsdake · CC BY-SA 3.0 · source
Name	Inabayama Castle
Native name	稲葉山城
Location	Mino Province, near modern Gifu Prefecture city of Gifu
Type	Mountain castle (yamajiro)
Built	c. 13th century (traditional)
Builder	traditional association with the Saitō clan and earlier local lords
Materials	stone, wood
Used	Sengoku period
Condition	reconstructed keep and museum (modern)
Occupants	Saitō Dōsan, Saitō Yoshitatsu, Saitō Tatsuoki, Oda Nobunaga
Battles	Siege of Inabayama (1567)
Map type	Japan Gifu Prefecture

Inabayama Castle was a strategically placed mountain fortress on Mount Inaba above the Kiso River valley in Mino Province, commanding routes between Owari Province, Echizen Province, and the Nakasendō. It served as the seat of the Saitō clan during the mid-16th century and became famous for its capture by Oda Nobunaga in 1567, an event that catalyzed subsequent campaigns against rivals including Takeda Shingen and Uesugi Kenshin. The site later received the name Gifu Castle under Nobunaga and remains a focal point of regional preservation and tourism in Gifu City.

Origin and Early History

The mountain stronghold traces traditional origins to minor warlords of the late Kamakura to Muromachi eras, associated with regional families and the shifting allegiances of Mino Province magnates, Toki Yoriyasu, and local castellans linked to trade on the Kiso River and routes toward Sekigahara. Early documentary mentions appear in provincial records alongside references to neighboring fortresses such as Mino Iwamura Castle and strategic posts controlling the Nakasendō and the Tōkaidō. The site’s hilltop position made it a focal point in disputes involving the Shiba clan, Saitō Myōchin, and later retainers who navigated conflicts with provincial authorities and neighboring warlords like Owari's Matsudaira clan and coastal powers based in Aichi Prefecture.

Sengoku Period and Saitō Clan

By the Sengoku period the stronghold was firmly in the hands of the Saitō clan, notably under the ambitious merchant-warrior Saitō Dōsan, who rose from kanpaku-era markets and provincial commerce to supplant the Toki clan in Mino. Dōsan’s rule and the succession conflicts involving Saitō Yoshitatsu and Saitō Tatsuoki intertwined with alliances and enmities involving figures such as Azai Nagamasa, Asakura Yoshikage, and the rising Oda clan of neighboring Owari Province. The castle functioned as a center for administration, military mustering, and negotiation with influential houses including the Ikko-ikki movements, Mori clan contacts, and merchant networks tied to riverine trade and the Ise Shrine pilgrimage routes.

Siege of Inabayama (1567) and Oda Nobunaga

The 1567 siege was a decisive operation launched by Oda Nobunaga after consolidating control of Owari Province and securing alliances with Azai Nagamasa (briefly) and other regional actors. Nobunaga’s forces executed night approaches and coordinated assaults involving retainers such as Toyotomi Hideyoshi (then known as Kinoshita Tōkichirō), who played a pivotal role in scaling slopes and breaching defenses, while commanders like Akechi Mitsuhide and Shibata Katsuie contributed to encirclement and siegecraft. The fall of the fortress ended Saitō rule — deposing Saitō Tatsuoki — and enabled Nobunaga to proclaim the renaming of the stronghold to Gifu Castle as part of his broader program of territorial consolidation and subsequent campaigns against opponents including Takeda Shingen, Uesugi Kenshin, and the entrenched Asakura clan.

Architectural Features and Layout

Perched atop a rugged spur, the castle employed classic yamajiro defenses: terraced baileys, dry moats (karabori), earthen ramparts, stonework foundations (ishigaki), and narrow approach paths adapted to the mountain’s topography. Gate complexes and kuruwa enclosures organized defenses around the main donjon site, integrating watch posts overlooking the Kiso River and the plains toward Owari Province. Contemporary accounts and archaeological surveys compare its layout to mountain castles such as Takeda Castle and Iwamura Castle, with adaptations reflecting Sengoku siegecraft employed by Nobunaga’s engineers and the castle’s role in commanding regional roadways like the Nakasendō and riverine corridors.

Later History, Renaming to Gifu Castle, and Modern Preservation

After Nobunaga’s capture the fortress was renamed Gifu Castle as part of Nobunaga’s symbolic program tied to his projected capital ambitions and his adoption of era- and place-naming practices also reflected in projects centered on Azuchi Castle and urban development in Kyoto. The site later saw changing stewardship through the Azai-Asakura conflicts, Toyotomi-era realignments, and the Tokugawa period’s reorganization of domains, including the rise of nearby Kanō Domain and links to officials in Edo. The original mountain stronghold fell into ruin over subsequent centuries; the modern hilltop features a reconstructed keep, a museum exhibiting artifacts connected to Saitō Dōsan, Oda Nobunaga, and regional archaeology, and preservation efforts coordinated with Gifu Prefecture authorities, municipal heritage programs, and tourism initiatives. Annual cultural events and historical reenactments draw visitors alongside regional sites such as the Gifu Great Buddha, Cormorant fishing displays on the Nagara River, and preserved Nakasendō post towns, sustaining scholarly interest from historians of the Sengoku period, archaeologists, and heritage professionals.

Category:Castles in Gifu Prefecture Category:Sengoku period