Battle of Thyatira
366 CE.
Shown on the map at 38.921°, 27.836°.
The Battle of Thyatira was fought in 366 at Thyatira, Lydia (modern Turkey), between the army of the Roman Emperor Valens and the army of the usurper Procopius, led by his general Gomoarius.
Text from the Wikipedia article Battle of Thyatira, licensed CC BY-SA 4.0.