Battle of Gifu Castle (1600)

The Battle of Gifu Castle, fought on August 22–23 in Keichō 5 (1600) at Gifu Castle (present-day Gifu City, Gifu Prefecture, atop Kinkasan), was a crucial preliminary engagement fought less than a month before the Battle of Sekigahara, which would determine the fate of the realm. The Eastern Army (Tokugawa Ieyasu's faction), led by powerful commanders including Fukushima Masanori and Ikeda Terumasa, launched an assault on Gifu Castle, which had been functioning as a stronghold of the Western Army (Ishida Mitsunari's faction). The castle fell in just two days. This rapid victory held immense strategic significance in determining the course of the main Battle of Sekigahara; and as a symbolic act, it epitomizes the end of the Sengoku period—the historical irony that the great castle Oda Nobunaga had built and developed as the base for his "Tenka Fubu" (Military Rule Over All Lands) became the final battlefield.

**Oda Hidenobu: The Tragic Position of "Sanbōshi"**

The lord commanding Gifu Castle, Oda Hidenobu, occupied a position of singular tragedy in Sengoku history. Hidenobu was known by the childhood name "Sanbōshi" and was the direct grandson of Oda Nobunaga, who fell to sudden death in the Honnōji Incident of 1582.

At the Kiyosu Conference in the sixth month of Tenshō 10 (1582), Sanbōshi was elevated as heir apparent to the Oda house. Yet in the power struggles that followed, Sanbōshi was progressively marginalized. As Toyotomi Hideyoshi consolidated his grip on the realm, Sanbōshi, now known as Hidenobu, remained as lord of Mino's Gifu Castle but possessed virtually no real political authority.

On the eve of Sekigahara in Keichō 5 (1600), Hidenobu chose to align with the Western Army faction led by Ishida Mitsunari. Behind this choice lay, it is said, resentment toward Tokugawa Ieyasu and the Western Army's professed aim of preserving Toyotomi rule. Yet this decision would bring about the destruction of Gifu Castle and Hidenobu's own downfall. The castle Nobunaga, his grandfather, had developed as the foundation of his unification campaign fell in the age of his grandson—becoming instead a symbol of the end of "Nobunaga's realm." This historical irony, in which the castle became the stage for the termination of Nobunaga's line as an independent power, stands as a fitting tragic denouement to the end of the Sengoku age.

**Gifu Castle's Strategic Importance: The Key to Mino Province**

Gifu Castle was a mountaintop fortress located at the summit of Kinkasan (329 meters elevation) and functioned as the political and military center of Mino Province. When Oda Nobunaga acquired this castle and renamed it "Gifu" (Eiroku 10, 1567), the name "Gifu," derived from classical Chinese texts, was said to signify the "starting point of realm unification."

In the tension of Keichō 5, Gifu Castle occupied a position near the intersection of the Nakasendō and Tōkaidō roads linking east and west, making it the most critical obstacle to westward movement for the Eastern Army. To capture Gifu Castle meant, for the Eastern Army, to control Mino Province and to open the path for advance westward from Owari and Mikawa.

For the Western Army, too, Gifu Castle served as an outpost defending the supply and communication routes to Ōgaki Castle (where Ishida Mitsunari's main forces were garrisoned). If Gifu Castle fell, Ōgaki Castle faced the danger of encirclement and might be forced to retreat toward Sekigahara—and this is precisely what came to pass.

**The Lightning Capture: Two Days of Combat**

On August 22, the Eastern Army's commanders launched a coordinated assault on Gifu Castle. Fukushima Masanori's forces crossed the Nagara River and pressed toward the castle town; Ikeda Terumasa's forces moved to encircle from another direction. The castle garrison is reported to have numbered about 6,000, yet they faced numerical inferiority against 30,000–40,000 Eastern Army troops.

Hidenobu fought with determination initially, but the defensive lines protecting the castle town were breached one after another, and by August 23 the attackers had reached the main citadel at the mountain's summit. The castle's fall in just two days shocked those who witnessed it. Some thirty-three years had passed since Nobunaga renamed it "Gifu," and the city that once symbolized realm unification fell with unexpected swiftness.

Oda Hidenobu surrendered and was spared by the Eastern Army commanders. Afterward, Hidenobu was ordered to withdraw to Kōyasan and died there in Keichō 10 (1605) at a young age.

**The Fall of Gifu Castle and Its Impact on Sekigahara**

The lightning-swift capture of Gifu Castle profoundly influenced the outcome of the Battle of Sekigahara (September 15). Ishida Mitsunari, the Western Army's supreme commander, had entered Ōgaki Castle anticipating a decisive engagement at Sekigahara, but the fall of Gifu Castle allowed the Eastern Army to advance westward with speed. Moreover, the news of this defeat could not have failed to inflict psychological turmoil upon the other Western Army commanders. One of the Western Army's principal justifications—"Sanbōshi, the blood of Oda Nobunaga"—was lost, casting a shadow upon Western Army morale.

Viewing the Battle of Gifu Castle as a preliminary engagement before Sekigahara, the characteristic of the Eastern Army's strategy lay in the thoroughness of its piecemeal destruction. The succession of victories in which the Toyotomi loyalists Fukushima Masanori and Ikeda Terumasa, now fighting for Ieyasu's "realm conquest," destroyed the Western Army's outlying strongholds one by one, was itself the process determining who would inherit the realm after Hideyoshi's passing.

**The Battle of Gifu Castle from the Perspective of Japanese Swords: A Decisive Battle in the Heartland of Mino Blades**

Mino Province (present-day Gifu Prefecture), the stage of the Battle of Gifu Castle, holds special significance in the history of Japanese swords. The "Mino school" ranked among the "Five Great Traditions of Blades"—alongside the Bizen, Sōshū, Yamashiro, and Yamato traditions—and the regions around Seki and Gifu were centers where numerous swordsmiths congregated.

The swordsmiths known as "Seki Magoroku" supplied the highest quality combat-ready blades from the Muromachi period through the Sengoku period, and the smiths renowned for the "Three Cryptomeria of Mino" hamon were beloved by warlords throughout the realm. It is highly probable that the samurai of both the Eastern and Western armies who fought at Gifu Castle carried Mino blades produced in this region at their waists.

Oda Nobunaga collected many renowned blades during his tenure as lord of Gifu Castle. In the period when Nobunaga held Gifu (1567–1582), many masterworks—including the renowned blade "Sōza Samonji" and "Yagen Tōshirō"—gathered at Gifu Castle. Hidenobu may have inherited some of these, but with the fall of the castle, their fate became unknown.

Masterworks by celebrated smiths of the Yamashiro and Raiden schools, such as "Fudō Kuniyuki," passed from hand to hand among warlords throughout the Sengoku conflicts. The fall of Gifu Castle was symbolic of a facet of Mino blade culture, accumulated during the age of Nobunaga, being swept away by the tides of history.

**The Battle of Gifu Castle and the Blades of Warlords: The Sword Aesthetics of Fukushima Masanori and Ikeda Terumasa**

Fukushima Masanori and Ikeda Terumasa, the leading commanders of the Eastern Army who directed the assault on Gifu Castle, were both renowned as fierce warriors and "protégés" of Toyotomi Hideyoshi.

Fukushima Masanori earned his reputation as one of the "Seven Spears of Shizugatake," and his martial prowess was demonstrated in both spear and sword. Though accounts exist of the renowned spears Masanori favored, it is likely he preferred sturdy, combat-focused Bizen and Mino blades for his swordsmanship.

Ikeda Terumasa, known as the "Middle Counselor of Harima," was a capable commander celebrated for the great renovation of Himeji Castle. Terumasa's interest in blades was high, and many renowned swords are transmitted to have resided within Himeji Castle. It cannot be ruled out that among the blades Terumasa acquired following the assault on Gifu Castle were Mino blades connected to Oda Nobunaga.

**Gifu Castle Ruins and the Modern Era: Historical Sites Conveying the End of Sengoku**

Present-day Gifu Castle (at the summit of Kinkasan) features a reinforced concrete reconstruction of the main tower completed in Shōwa 31 (1956), which has become a symbol of Gifu City. The original main tower was dismantled after the Battle of Sekigahara (1601), and its materials were repurposed in the construction of Kanō Castle (in southern Gifu City).

From the Kinkasan summit, reached by ropeway, the Nagara River and the Nōbi Plain stretch into view, allowing visitors to contemplate the Sengoku landscape that Nobunaga and Hidenobu once surveyed. The castle displays materials related to Nobunaga, and the Gifu City Historical Museum (at the foot of Kinkasan) introduces the history of Gifu during the ages of Nobunaga and Hidenobu, as well as Mino blade culture.

The Battle of Gifu Castle, through the grand significance embedded in the place name "Gifu" born of Nobunaga's ambitions and the tragic denouement of its fall in his grandson's generation, stands as one of the most dramatically realized expressions of the end of the Sengoku age. For blade enthusiasts, visiting the birthplace of the Mino tradition and walking through the "homeland of Mino swords" while feeling the tension of the eve of Sekigahara and the unification dreams of Nobunaga's era offers one of the finest ways to understand the history of Japanese swords firsthand.