Ishida Mitsunari

Mitsunari was taken into service as a page at the age of fifteen or sixteen by Hideyoshi who was then residing at Nagahama Castle. He served him with unfailing loyalty, and demonstrated considerable intelligence and skill. He became top of Hideyoshi's bureaucracy.
Mitsunari was a brilliant administrator rather than a general. He disciplined the lower soldiery, organised the populace, and conducted shrewd negotiations with subordinate daimyo. On the death of Hideyoshi in 1598, discord emerged among the restive daimyo, which led to the Battle of Seki-ga-Hara. Mitsunari was unable to bring his own army through to victory.
He devoted himself to Hideyoshi's young successor, Hideyori, and was wary of Tokugawa Ieyasu, who most menaced the Toyotomi line. Ieyasu ignored Toyotomi laws and so Mitsunari organised an alliance to attack him. There followed the Battle of Seki-ga-Hara in 1600, which polarised all the states. Mitsunari and the Eastern Alliance were defeated owing to the treachery of Kobayakawa Hideaki, who switched sides in mid-fight. Mitsunari was seized during the battle, led to Kyoto, and there put to death.