Mōri Terumoto
The Siege of Kōzuki Castle occurred in 1578, when the army of Mōri Terumoto attacked and captured Kōzuki Castle (上月城) in Harima Province. Terumoto ordered his uncle, Kobayakawa Takakage, to bring reinforcements and he showed up with a force 30,000 strong. Narinaga and his first son, Motoyoshi, who was 21 years old at the time were present at the battle and helped bring down the castle. At Hiroshima Museum there is a letter of thanks from Mōri Terumoto to Narinaga for his son's participation in the battle. Kōzuki Castle had been taken by Hashiba Hideyoshi the previous year and entrusted to Amago Katsuhisa. When it fell to Mōri Motonari, Katsuhisa committed suicide (seppuku) and his loyal and heroic general Yamanaka Yukimori was captured and killed in the battle. Yukimori was the samurai who had killed Narinaga's family member, Kikuchi Otohachi, many years before.