Born in Nakamura, Aichi District, Owari Province (present-day Nakamura Ward, Nagoya), he served Toyotomi Hideyoshi from childhood due to their shared hometown connection. At the Battle of Shizugatake in 1583 he distinguished himself as one of the Seven Spears and built his military reputation. In 1588 he was granted the southern half of Higo Province (190,000 koku, later the entire province) and built the new Kumamoto Castle. He took part in both invasions of Korea — the Bunroku Campaign of 1592 and the Keicho Campaign of 1597 — capturing fortresses in the north. The legend of Kiyomasa's tiger hunt is based on a story of his killing a tiger far to the north (near the Manchurian border) during these Korean campaigns. At Sekigahara in 1600 he joined the eastern (Tokugawa) forces, pressuring the western-aligned lords of Kyushu, and after the battle became a great lord with the entire Higo Province at 520,000 koku. He found himself in the difficult position of maintaining ties with the Tokugawa shogunate while supporting Toyotomi Hideyori, and in 1611 he mediated the meeting between Ieyasu and Hideyori at Nijo Castle; shortly afterward he fell ill and died in June of the same year at age 50. Rumors of poisoning circulate but the truth is unknown. The formidable construction techniques of Kumamoto Castle were later proven during the Satsuma Rebellion.