Yamanouchi Kazutoyo

Japanese feudal lord

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July 15, 2026

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Yamanouchi Kazutoyo was a prominent Japanese feudal lord who rose to prominence during the turbulent Sengoku period. He served under Toyotomi Hideyoshi, a key figure in unifying Japan, and was rewarded with a small fief for his battlefield successes. After Hideyoshi's death, Kazutoyo shifted his allegiance to Tokugawa Ieyasu, aiding him at the pivotal Battle of Sekigahara in 1600. This strategic move led to Ieyasu granting Kazutoyo the significant fief of Tosa. The Yamanouchi family, under Kazutoyo's leadership, remained loyal to the Tokugawa shogunate throughout its rule, which lasted until 1868.1234

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Yamanouchi family
…Yamanouchi family’s fortunes began with Yamanouchi Kazutoyo (1546–1605). For his successes on the battlefield in the service of Toyotomi Hideyoshi, then the most powerful general in Japan, Kazutoyo was rewarded with a small fief. After Hideyoshi’s death, Kazutoyo switched his loyalty to Tokugawa Ieyasu (1543–1616), whom he aided at the…
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…Yamanouchi family’s fortunes began with Yamanouchi Kazutoyo (1546–1605). For his successes on the battlefield in the service of Toyotomi Hideyoshi, then the most powerful general in Japan, Kazutoyo was rewarded with a small fief. After Hideyoshi’s death, Kazutoyo switched his loyalty to Tokugawa Ieyasu (1543–1616), whom he aided at the…
Read More