Battle of Châlons
274 CE.
Shown on the map at 48.958°, 4.365°.
The Battle of Châlons, also known as the First Battle of the Catalaunian Plains, was fought in 273 or 274 in the land of the Catalauni, at an unknown location probably not far from the present-day Châlons-en-Champagne, France. In the battle, the Roman Emperor Aurelian defeated the Emperor Tetricus I of the Gallic Empire, whose territories were thus recovered by the Roman Empire after 14 years of separation.
Text from the Wikipedia article Battle of Châlons (274), licensed CC BY-SA 4.0.