Battle of the Vozha River
1378 CE.
Shown on the map at 54.717°, 39.444°.
The Battle of the Vozha River (Russian: Битва на реке Воже, romanized: Bitva na reke Vozhe) was a battle during the Great Troubles, fought between the Principality of Moscow and Mamai's faction within the Golden Horde on 11 August 1378. Mamai sought to punish Dmitri Ivanovich of Moscow (who had not yet received his nickname Donskoy) for refusing to pay the tribute.
Text from the Wikipedia article Battle of the Vozha River, licensed CC BY-SA 4.0.