Hideyoshi Tokugawa (1579-1651), the second general of the Tokugawa shogunate during the Edo period in Japan, was the eldest son of Tokugawa Ieyasu, the founder of the shogunate. He inherited the family governor in 1604 and became the actual ruler of Japan.
In this fictional historical story, the key factor that has been changed is that Hideyoshi Tokugawa survived his illness and continued his rule as the shogunate general. This altered the course of history and led to significant changes in Japan's feudal system and relations with foreign powers.