Battle of Sakainehara
1479 CE.
Shown on the map at 35.832°, 139.953°.
The Battle of Sakainehara (境根原合戦, Sakainehara Kassen) was fought in 1478 between the forces of Chiba Noritane (千葉孝胤) and the forces of Ōta Dōkan and Chiba Yoritane (千葉自胤).
Text from the Wikipedia article Battle of Sakainehara, licensed CC BY-SA 4.0.