Battle of Okehazama
During the Muromachi period, Sunpu was the capital of the Imagawa clan. The Imagawa were defeated at the Battle of Okehazama, and Sunpu was subsequently ruled by Takeda Shingen, followed by Tokugawa Ieyasu. However, Toyotomi Hideyoshi relocated Ieyasu, and installed Nakamura Kazutada to rule Sunpu. After the Toyotomi were defeated in the Battle of Sekigahara, Ieyasu recovered Sunpu, reassigning it to his own retainer, Naitō Nobunari in 1601. This marked the start of Sunpu Domain.