It was regarded as one of the seven main strongholds of the Kantō region Oshi Castle was completed by Narita Akiyasu around 1479.

In 1590, Toyotomi Hideyoshi dispatched Ishida Mitsunari with an army of 23,000 troops to seize the castle.

Despite Mitsunari’s impressive construction of 28 kilometers of dikes and torrential rains, the castle still held and its defenders only surrendered after receiving word that their overlords had been defeated in the siege of Odawara.

The castle town prospered during the Edo period from its proximity to the Nakasendō highway, and location on the Tone River.

Following the Meiji restoration, all of the structures of the castle were destroyed and its site turned into a public park.