Yamamoto Gonnohyōe was a prominent Japanese military leader during the late Edo period and early Meiji period. He is best known for his role in the Boshin War, a civil war in Japan that took place from 1868 to 1869. Gonnohyōe was a key figure in the Tokugawa shogunate and later supported the imperial forces, contributing to the modernization of Japan's military. After the Meiji Restoration, Gonnohyōe continued to serve in various military capacities, helping to shape Japan's new army. His efforts were instrumental in transitioning Japan from a feudal society to a modern state, influencing the country's military strategies and organization during a pivotal time in its history.