 Mitsunari also participated in the 1590 campaign against the Hōjō clan, where he commanded the Siege of Oshi and captured Oshi Castle and in 1591 fought againts Kunohe Rebellion.Later, he served in the Japanese invasions of Korea (1592–98).Mitsunari was a leader of bureaucrats in Hideyoshi's government, and was known for his unbending character.