Born in 1540 in Owari Province as Hideyoshi's half-brother (different fathers). His childhood name was Koichiro; he later took the name Hidenaga. From early on he stood at Hideyoshi's side as Hideyoshi rose through service to the Oda, from the legendary overnight construction of Sunomata Castle through the campaigns against western Japan, Shikoku, and Kyushu. He excelled not only in military matters but also in governance and diplomacy, effectively serving as the manager and backbone of the Toyotomi regime. Holding nearly a million-koku domain at Yamato-Koriyama, he was called the "Dainagon of Yamato." His even-handed, sincere character earned deep trust among all the daimyo, and he was the only person who could frankly remonstrate with Hideyoshi when he overreached. When he died of illness in 1591 at age 51, the Toyotomi regime rapidly lost cohesion and veered toward its tragic end through the Korean invasions and the Hidetsugu Incident.