Imagawa Yoshimoto (今川 義元, 1519 – June 12, 1560) was a pre-eminent daimyō (feudal lord) in the Sengoku period Japan. Based in Suruga Province, he was one of the three daimyōs that dominated the Tōkaidō region.
He died in 1560 while marching to Kyoto to become Shogun. He was killed in the village of Dengakuhazama in Okehazama by Oda Nobunaga.
9th head of Suruga-Imagawa family
|Preceded by||Imagawa Ujiteru|
|Succeeded by||Imagawa Ujizane|
Sunpu, Suruga Province, Japan
June 12, 1560 (aged 41)|
Okehazama, Owari Province, Japan
Yoshimoto was born in 1519, the third son of Imagawa Ujichika of the Imagawa clan-which claimed descent from Emperor Seiwa (850–880). His childhood name was Yosakimaru (芳菊丸). His family branched from Minamoto clan by the Ashikaga clan. As he was not the eldest son, he was not an heir to his father's lordship. As a result, the young boy was sent to a temple where his name was changed to Baigaku Shōhō (梅岳承芳) or Sengaku Shōhō (栴岳承芳). In 1536, his older brother Ujiteru died suddenly, unleashing successional disputes. His elder half-brother, Genkō Etan (玄広恵探), tried to seize the lordship, but the clan split into two factions. Yoshimoto's faction argued he was the rightful heir because Yoshimoto's mother was the consort of Ujichika. Genkō Etan's faction disputed this based on Genkō's seniority, and that his mother was a member of the Kushima family. However, the Genkō faction was eliminated in the Hanagura Disturbance (花倉の乱 Hanagura-no-ran). Baigaku Shōhō changed his name to Yoshimoto at this point and succeeded the clan.
After Yoshimoto succeeded to family headship, he married the sister of Takeda Shingen of Kai. This allowed Yoshimoto to cement an alliance with the Takeda when he helped Shingen imprison his father, Takeda Nobutora, in 1540. Soon after, Yoshimoto fought against the Hōjō of Sagami. In 1542, Yoshimoto began his advance into Mikawa Province, in an effort to fight the growing influence of Oda Nobuhide in that region, but was defeated in the Battle of Azukizaka (1542). In campaigns over the course of the ensuing decades, Yoshimoto wrested control over the Suruga, Totomi, and Mikawa provinces.
In 1552, Shingen's son, Takeda Yoshinobu, married Yoshimoto's daughter. Yoshimoto and the Hōjō clan reached a peace agreement in 1554 with the marriage of Yoshimoto's son Ujizane to the daughter of Hōjō Ujitsuna. In 1558, Yoshimoto left the clan's political affairs in Ujizane's hands, in order to focus on dealing with the advance westward into Mikawa.
In the summer of 1560, after forming a three-way alliance with the Takeda and the Hōjō, Yoshimoto headed out to the capital with Tokugawa Ieyasu (then known as Matsudaira Motoyasu) of Mikawa in the vanguard. Despite having a strong force of 25,000, Yoshimoto deliberately announced that he had 40,000 troops. While this statement put fear in many factions, Oda Nobunaga of Owari Province saw through it. (Some historical sources support the claim of 40,000.)
With many victories, Yoshimoto's army was letting its guard down, celebrating with song and sake. A surprise attack by the Oda army of 3,000 following a downpour left Yoshimoto's army in complete disorder. Two Oda samurai (Mōri Shinsuke and Hattori Koheita) ambushed the Imagawa army and killed Yoshimoto, in the village of Dengakuhazama.:37–39
Imagawa Ujizane succeeded to family headship after Yoshimoto's death, but the Imagawa clan fell from power. Ujizane was later summoned by Tokugawa Ieyasu and became a kōke in the administration of the Tokugawa clan. Yoshimoto's niece was Lady Tsukiyama, the wife of Tokugawa Ieyasu.
| 9th Suruga-Imagawa family head
A female version of Yoshimoto appears in anime The Ambition of Oda Nobuna. In this version, instead of dying Yoshimoto is spared and later installed as a figurehead Shogun to legitimize Nobuna's claim to Kyoto.