Ishida Mitsunari (石田 三成 1560 – November 6, 1600) was a samurai who led the Western army in the Battle of Sekigahara following the Azuchi-Momoyama period of the 17th century. Also known by his court title, Jibunoshō (治部少輔)
He was born in the north of Ōmi Province (which is now Nagahama, Shiga prefecture), and was the second son of Ishida Masatsugu, who was a retainer for the Azai clan. His childhood name was Sakichi (佐吉). The Ishida withdrew from service after the Azai's defeat in 1573. According to legend, he was a monk in a Buddhist temple before he served Toyotomi Hideyoshi, but the accuracy of this legend is doubted since it only came about during the Edo period.
Mitsunari met Toyotomi Hideyoshi when the former was still young and the latter was the daimyo of Nagahama. When Hideyoshi engaged in a campaign in the Chūgoku region, Mitsunari assisted his lord in attacks against castles like the Tottori Castle and Takamatsu Castle (in present-day Okayama).
After Hideyoshi seized power, Mitsunari became known as a talented financial manager due to his knowledge and skill at calculation. From 1585 onward, he was the administrator of Sakai, a role he took together with his elder brother Ishida Masazumi. He was appointed one of the five bugyo, or top administrators of Hideyoshi's government. Hideyoshi made him a daimyo of Sawayama in Ōmi Province, a five hundred thousand koku fief (now a part of Hikone). Sawayama Castle was known as one of the best-fortified castles during that time.
Mitsunari was a leader of bureaucrats in Hideyoshi's government, and was known for his rigid character. Though he had many friends, he was on bad terms with some daimyo that were known as good warriors, including Hideyoshi's relatives Fukushima Masanori and Katō Kiyomasa. After Hideyoshi's death, their conflict worsened. The central point of their conflict was the question whether Tokugawa Ieyasu could be relied on as a supporter of the Toyotomi government, whose nominal lord was the child Toyotomi Hideyori.
In 1600, the Battle of Sekigahara was fought as a result of this political conflict. Mitsunari succeeded in organizing an army led by Mori Terumoto. But the coalition following Tokugawa Ieyasu was greater, and the battle resulted in Mitsunari's defeat.
After his defeat, he sought to escape, but was caught by villagers. He was beheaded in Kyoto. After execution, his head, severed from his body, was placed on a stand for all the people in Kyoto to see. However, a rumor has it that after a few days, his head mysteriously disappeared . Other daimyo of the Western army, like Konishi Yukinaga and Ankokuji Ekei were also executed.
Mitsunari had three sons (Shigeie, Shigenari and Sakichi) and three daughters (only the younger girl's name is known, Tatsuko) with his wife, and another child from a mistress.
See People of the Sengoku period in popular culture