Battle of Placentia
271 CE.
Shown on the map at 45.050°, 9.700°.
The Battle of Placentia was fought in 271 between a Roman army led by Emperor Aurelian and the Juthungi tribe, near modern Piacenza. The result was Juthungian victory.
Text from the Wikipedia article Battle of Placentia (271), licensed CC BY-SA 4.0.