The two-week-long siege of Inabayama Castle marked the dramatic climax of Oda Nobunaga’s campaign to assert control over Mino Province and decisively crush the Saitō clan. It was during this operation that Toyotomi Hideyoshi, then known as Kinoshita Tōkichirō, first shone brightly in competition with Nobunaga—emerging as the future heir to Japan’s unification.
Saitō Dōsan (1494–1556), the founder of the Saitō line, epitomized the gekokujo daimyo of the Sengoku era: a schemer, backstabber, and formidable warrior. By 1552, through intrigue and military might, he had seized control of Mino Province—expelling the Toki clan—and earned the notorious nickname “Serpent Daimyo of Mino.” To reinforce his influence in neighboring Owari, he married off his daughter Keichō to Oda Nobunaga. In 1555, Dōsan’s adopted son, Saitō Yoshitatsu, believing he had been passed over for succession, rebelled and defeated Dōsan at the Battle of Nagaragawa in 1556, resulting in Dōsan’s beheading.
This event gave Nobunaga a nominal justification for invading Mino: according to some accounts, Dōsan had named him heir shortly before his death. However, lacking sufficient power at the time, the Oda-Saitō conflict remained a border dispute. Yoshitatsu then succumbed to leprosy in 1561 and was succeeded by his ineffective son, Saitō Tatsuoki—whose cowardice eroded the loyalty of many retainers and allowed Nobunaga to further extend his influence.
Seizing the opportunity, Nobunaga transferred his base to Komaki Castle and, in 1561, defeated Tatsuoki’s forces at the Battle of Moribe. Although some sources hint at an earlier 1564 attempt on Inabayama Castle, official records like the Shinchō Kōki recognize the 1567 siege as the true turning point in Nobunaga’s Mino campaign.
Beginning in 1564, Hideyoshi worked diligently to secure the loyalty of Saitō vassals—either through alliance or bribes—winning over the powerful “Triumvirate of Western Mino” composed of Ujiie Naotomo, Andō Morinari, and Inaba Yoshimichi.
In 1566, acting on Hideyoshi’s suggestion, Sunomata Castle was rapidly erected mere kilometers from Inabayama, serving as a strategic staging point for the upcoming assault.
In autumn 1567, Nobunaga’s army crossed the Kiso River and set up camp about five kilometers south of Inabayama. They were soon joined by defectors from Saitō’s retinue, substantially bolstering their ranks. Skirmishes erupted with the defenders’ advance guard as the army neared the mountain fortress—constructed atop Mount Inaba, known for its sheer northern face and a winding southern path dubbed the “Trail of One Hundred Bends.” Due to insufficient trust in Tatsuoki, command of the defense fell to Takenaka Hanbei (Shigeharu).
To clear the field of operations, Hideyoshi’s vanguard burned the castle town of Inoguchi and occupied a nearby hill. While setting up siege lines, Hideyoshi gathered intelligence—interviewing locals and receiving vital guidance from his retainer Horio Yoshiharu, a native who knew a nearly forgotten northern route. Legends say he once bested a wild boar in combat as a child, impressing Nobunaga, who valued his bravery.
Nobunaga was not one for prolonged sieges: his forces harassed the defenders daily, gradually tightening their grip. Hideyoshi proposed a daring plan: under cover of darkness, a small unit would ascend the nearly impossible north slope, infiltrate the castle, and open the gates from within. Nobunaga approved, assigning Hideyoshi to lead the commando team and Kuroda Kanbei to coordinate the main southern attack.
That night, guided by Horio, Hideyoshi’s team successfully negotiated the steep northern terrain and entered the castle. Simultaneously, the southern assault commenced. Fires erupted in the magazine and powder store, creating panic among the defenders, who believed they were under attack from both sides. In the ensuing chaos, Hideyoshi’s men opened the gates—and the main army poured in.
Miraculously, Nobunaga granted rare clemency: Tatsuoki was exiled to Ise Province, later fighting against Nobunaga under the Asakura clan before dying in battle at Tonezaka in 1573. Meanwhile, Takenaka Hanbei proved his worth and accepted a position under Hideyoshi.
Nobunaga relocated his headquarters from Komaki to the newly captured castle, renaming both the fortress and the adjoining town Gifu. Over time, Gifu Castle was significantly expanded and became the political and military center of the region.
This siege also gave rise to Hideyoshi’s famous banner—the “Golden Gourd.” His troops carried hollowed gourds (suikyo) as water flasks during the assault. Once the gates were opened, they skewered the gourds onto spears signaling to Kuroda Kanbei that the breach was secure. In honor of the success, Hideyoshi later adopted a gourd-shaped umajirushi (personal standard). While popular media often depict this standard with many gourds, historical account supports only one.
See also
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The Third Siege of Takatenjin Castle
The history of the castle prior to the conflict between the Tokugawa and Takeda clans is rather unclear. According to one version, the castle was built in 1416, when Imagawa Sadayoshi (1325–1420) was governor of Suruga Province and half of Totomi Province. Allegedly, it was he who ordered Imagawa Norimasa (1364–1433) to build this fortification. However, no reliable evidence has been found to support this. Another version is considered more plausible, according to which the castle was built during the conquest of Totomi Province at the end of the 15th century by Imagawa Ujitsuna (1473–1526) and his general Ise Shinkuro (Hojo Soon). In this case, another of Ujitsuna's generals, Kusima Masashige (1492–1521), is considered responsible for the construction.
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Battle of Mimigawa
In 1556, the Shimazu clan launched a campaign aimed at systematically conquering the island of Kyushu. In the same year, the province of Osumi was annexed and a war began with the Ito clan for control of the province of Hyuga. In 1577, Ito Yoshisuke was defeated and fled north, where he sought help from Otomo Sorin, the Christian daimyo of Bungo Province.
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The Siege of Kozuki Castle
The battle for Kozuki Castle was a consequence of Oda Nobunaga's expansion in the Chugoku region. Toyotomi Hideyoshi was appointed to lead the campaign, which aimed to weaken the influence of the Mori clan in these lands. Under his command were famous samurai: Kuroda Kanbei, Takenaka Shigeharu, and Hachisuka Koroku. Amago Katsuhisa, who cherished the hope of one day restoring the Amago clan's lost dominance in western Japan, also joined Oda's army.
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The Siege of Nagashino Castle
Despite his reputation as a failure, created by 20th-century popular culture, especially cinema, Takeda Katsuyori (1546–1582) was in fact a brave warrior and talented commander. However, he always remained in the shadow of his great father, the legendary Takeda Shingen. After Shingen's death, Katsuyori sought to at least equal him, if not surpass him. Therefore, his actions were not always determined by pragmatic calculation. This character trait greatly influenced the subsequent events that led to the demise of the Takeda clan.
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Siege of Nagashima Fortifications
The Buddhist peasant movement Ikko-Ikki, which emerged in the 15th century, had grown considerably stronger and larger by the middle of the following century. It had effectively turned into a large feudal army used for territorial conquests. The Ikko-ikki fought fiercely not only against other branches of Buddhism, but also against the provincial daimyo and the central government.
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The Second Battle of Konodai
Hojo Ujiasu (1515–1571), one of the greatest representatives of the Hojo clan, spent almost his entire life at war. His possessions were in a difficult position: they were surrounded on all sides by aggressive neighbors ready to attack at any moment. In implementing his plans to expand the Hojo clan's influence in the Kanto region, Ujiasu was forced to confront well-known and powerful opponents—the Uesugi and Takeda clans. In the east, his main rival was the Satomi clan.
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The Fourth Battle of Kawanakajima
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Battle of Tonamoto (Nagahama)
At the beginning of the Sengoku Jidai period, the Teshokabe clan was one of the smaller clans in Tosa Province. Its neighbors were constantly at war with each other, engaging in endless skirmishes. Among them, Yosokabe Kunitika stood out as a military strategist of extraordinary talent. It was thanks to these abilities that he managed to defeat the neighboring clans step by step by the middle of the 16th century, expanding the influence of his clan. At that time, the clan's headquarters was Oko Castle.
