
Imagawa Yoshimoto, a formidable daimyo of Suruga (modern-day Shizuoka Prefecture), held a prominent position among the three influential warlords in the central Japan region, known as Tokai. His lineage was believed to trace back to a branch of the noble Minamoto clan, and Yoshimoto, displaying a nobler image than a typical warrior, blackened his teeth, shaved his eyebrows, and was carried in an ornate palanquin.
Born as the third son of Imagawa Ujichika, the 10th head of the Imagawa clan, Yoshimoto was initially sent to a temple to become a monk. Following his father's demise in 1526 and the sudden death of his elder brother Ujiteru a decade later, the Imagawa clan faced internal divisions. Factions supporting Yoshimoto engaged in war against those backing an elder half-brother, resulting in Yoshimoto's triumph in June 1536.
Upon assuming leadership of the Imagawa clan, Yoshimoto strategically married the sister of rival warlord Takeda Shingen, solidifying an alliance that kept Shingen from encroaching on Imagawa territories. In 1552, the alliance was further strengthened when Shingen's son Yoshinobu married Yoshimoto's daughter. Additionally, a political marriage was arranged between Yoshimoto's son and heir, Ujizane, and the daughter of rival warlord Hojo Ujitsuna in 1554.
In 1542, Yoshimoto set his sights on the prosperous Mikawa region controlled by the Matsudaira, later to become the Tokugawa clan. The Imagawa territories expanded over the years to include Suruga, Totomi (now Shizuoka Prefecture), and Mikawa (eastern Aichi Prefecture). Thereafter, Yoshimoto aimed for Kyoto, necessitating the conquest of Owari Province (western Aichi Prefecture), held by Oda Nobunaga.
In 1560, Yoshimoto, with a claimed force of 40,000 (an exaggeration), led 25,000 troops into Owari. The vanguard included a 19-year-old samurai named Matsudaira Motoyasu, who later became Tokugawa Ieyasu. The young Ieyasu, a political hostage of the Imagawa since age nine, had been sent ahead to deliver supplies to Odaka Castle.
The unexpected assault by Oda during the battle of Okehazama troops caught Imagawa and his men off guard. Initially thinking it was a drunken brawl, Yoshimoto investigated and was stunned to find Oda forces approaching. Despite resisting an attack by Mori Shinsuke, Yoshimoto was eventually tackled by Hattori Koheita, an Oda samurai, who took the daimyo's head. Yoshimoto Yoshimoto succumbed to the attack at the age of 41.
While there are several gravesites associated with Imagawa Yoshimoto, his remains are said to be interred at Daisei-ji Temple in Toyokawa, Aichi Prefecture.
See also
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Ouchi Yoshioki

Ouchi Yoshioki, the ruler of the provinces of Suo, Nagato, and Iwami, was one of the most capable military commanders and politicians of the late 15th and early 16th centuries. The son of Ouchi Masahiro, he governed from his residence in Yamaguchi in the province of Suo. In 1499, Yoshioki gave refuge to Shogun Ashikaga Yoshitane, who had been driven out of Kyoto by Hosokawa Masamoto. Shogun Yoshizumi, Masamoto’s protégé, ordered the lords of Kyushu to unite their forces against Yoshioki; however, they did not dare to do so, fearing the power of a man who by that time controlled six provinces. Having gathered a substantial army, Yoshioki marched from his native Suo toward Kyoto in order to restore Shogun Yoshitane to power.
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Otomo Sorin

Ōtomo Yoshishige came from a noble lineage, being the eldest son of Ōtomo Yoshiaki, the ruler of Funai Province. The roots of the Ōtomo family traced back to Fujiwara Hidesato, the adopted son of Nakahara Chikayoshi. Fujiwara served Minamoto Yoritomo during the Genpei War and took part in battles in Mutsu Province in 1189. In 1193, he was appointed shugo of Buzen and Bungo Provinces, after which he adopted a new surname—Ōtomo.
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Okudaira Sadamasa

Sadamasa was the son of Okudaira Sadayoshi and took part in several battles under Tokugawa Ieyasu, distinguishing himself in the Battle of Anegawa in 1570, where he took two heads. Around 1572 he was forced to enter the service of the Takeda clan, but after the death of Takeda Shingen in 1573 he returned to Tokugawa, leaving Tsukude Castle together with his men. As a result of this defection, Takeda Katsuyori ordered the execution of Sadamasa’s wife and brother, who were being held as hostages.
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Okubo Tadatika

Tadatika, the son of Okubo Tadayō, entered the service of Tokugawa Ieyasu at the age of eleven, and took his first head in battle when he was sixteen. After the establishment of the Tokugawa shogunate, he was appointed as a rōjū — a senior bakufu official — and was regarded as one of Ieyasu’s most trusted advisors, alongside Honda Masanobu. He is also known for his military chronicle Mikawa Monogatari, which describes Ieyasu’s rise to power and the early years of the Tokugawa shogunate.
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Okubo Nagayasu

Nagayasu was the second son of Okura Nobuyasu, a sarugaku theater actor from the Takeda clan. Takeda Shingen recognized the young man’s potential and took him into service, appointing him as a vassal to his general, Tsuchiya Masatsugu. During this period, Nagayasu changed his family name to Tsuchiya. He was entrusted with developing the Takeda clan’s gold mines as well as handling matters related to taxation.
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Nitta Yoshisada

Nitta Yoshisada was a loyal soldier of Emperor Go-Daigo, who in the 1330s attempted to restore direct imperial rule in Japan. The Nitta family was related to the Ashikaga house and was older in lineage. However, they did not join Minamoto Yoritomo at the start of his war with the Taira, as the Ashikaga did, and therefore did not receive high positions in the Kamakura shogunate. This may have been one of the reasons why Yoshisada rose against the Hōjō clan in 1333.
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Natsume Yoshinobu

Yoshinobu, a long-time vassal of the Matsudaira and Tokugawa clans, governed Hamamatsu Castle on behalf of the Tokugawa house. During the clashes between the Imagawa, Takeda, and Matsudaira clans, he served in the garrison of Nagasawa Castle and in 1562 took part in raids under the command of Itakura Shigezane. When, in 1563, a revolt of the Sōtō-shū sect followers broke out in Mikawa Province, Yoshinobu joined the rebels together with Honda Masanobu and Hachiya Sadatsugu.
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Nambu Nobunao

The Nambu clan was an ancient and powerful family that traced its lineage back to the Minamoto shoguns and had controlled a significant part of the Tohoku region in northern Honshu since the 12th century. Nobunao was born in Ikatai Castle, located in what is now the city of Iwate. He was the second son of Ishikawa (Nambu) Takanobu, the 22nd head of the Nambu clan. In 1565, Nobunao’s uncle, Nambu Harumasa, adopted him, brought him to Sannohe Castle, and named him his heir, later giving his daughter in marriage to him.
