On August 20, 1570, the Battle of Imayama unfolded in Kyushu. Similar to the renowned Battles of Okehazama (1560) and Kawagoe (1545), the Imayama clash stands as a remarkable instance of surprise attacks during the Sengoku Period.
The Otomo and Ryuzoji clans, long-standing rivals and dominant powers in northern Kyushu, found themselves in a fierce rivalry. In that fateful August of 1570, Otomo Sorin rallied an immense force of approximately 60,000 samurai, commanded by his younger brother, Chikasada. Their goal was to decisively defeat their rival, Ryuzoji Takanobu.
Anticipating the looming assault, Ryuzoji Takanobu guided a modest contingent into Saga Castle. As the Otomo forces laid siege to the castle, a pivotal realization dawned upon Nabeshima Naoshige, the master of Saga Castle. Recognizing the Otomo's overconfidence and lack of preparation due to their overwhelming numbers, he devised a countermove. Capitalizing on the cover of darkness, he stealthily led a small group out of the castle, embarking on a daring assault against Chikasada's headquarters. This audacious maneuver culminated in the demise of Chikasada himself. The impact of this unexpected strike sent shockwaves through the Otomo ranks, causing disorder and chaos. Bereft of leadership, the Otomo forces were compelled to retreat in disarray.
See also
-
The Rebellion of Fujiwara no Hirotsugu
Fujiwara no Hirotsugu was the son of Fujiwara no Umakai, one of the most important court officials of the Nara period. By 740, the Fujiwara clan had held the reins of government for several decades. However, in 735–737, Japan suffered a severe trial: the country was hit by a devastating smallpox epidemic. It coincided with a series of crop failures, and together, disease and famine claimed the lives of about 40% of the population of the Japanese islands. The consequences were particularly tragic for the aristocracy. The mortality rate among the court nobility exceeded that among the common people. All four Fujiwara brothers, who held the most important positions at court — Umakai, Maro, Mutimaro, and Fusasaki — died.
-
The Battle of Inogahara
By the summer of 1556, Oda Nobunaga no longer appeared to be the eccentric “great fool of Owari.” Four years earlier, in 1552, having just assumed the position of clan leader, he managed to defend his position: first in the Battle of Akatsuka, and then at Kayazu Fort. In 1553, together with his western neighbor and ally Saito Dosan, his father-in-law, Nobunaga successfully repelled an attack by the Imagawa clan on the border fort of Muraki. In 1554, he united his own branch of the family with the Kiyosu line. Step by step, the young military leader strengthened his position.
-
The Second Siege of Gassan-Toda Castle (1564–1565)
Mori Motonari (1497–1571), head of the powerful Mori clan, was one of the most influential daimyo in the Chugoku region, located in western Honshu. During the turbulent and violent Sengoku Jidai period, he waged continuous wars in an effort to expand his domain and strengthen his clan's power.
-
The Siege of Inabayama Castle
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.
-
The Siege of Wado Castle
In 1335, the Shiina clan built Uozu Castle as an auxiliary stronghold supporting Matsukura Castle. By 1570, it had fallen under the control of the Uesugi clan, rapidly emerging as a strategic fortress in Etchū Province. For many years, Kawada Nagataka served as its commander.
-
The siege of the Ishimama Honganji monastery
In Japanese history, the siege of Ishiyama Hongan-ji — the main stronghold of the Ikkō-ikki movement during Oda Nobunaga’s campaign — is considered the longest, lasting from August 1570 to August 1580.
-
The Battle of Norada
The Battle of Norada is a striking example of a clash during the Sengoku Jidai period, when numerical superiority did not always guarantee victory, even in open battle.
-
Battles of Kawanakajima
The Battles of Kawanakajima were a series of fierce conflicts during Japan's Sengoku period, waged between Takeda Shingen of Kai Province and Uesugi Kenshin of Echigo Province from 1553 to 1564. These battles centered around the strategic Kawanakajima plain, lying between the Sai and Chikuma rivers in northern Shinano Province, now within Nagano City. The rivalry began when Shingen took control of Shinano, forcing Ogasawara Nagatoki and Murakami Yoshikiyo to seek refuge with Kenshin, prompting repeated clashes.
