Siege of Lubusz
1012 CE.
Shown on the map at 52.426°, 14.535°.
The siege of Lubusz was a siege part of the German–Polish War that took place from 19 to 20 August 1012. It involved the Duchy of Poland led by Bolesław I the Brave against the Holy Roman Empire led by Henry II. It resulted in a Polish victory.
Text from the Wikipedia article Siege of Lubusz, licensed CC BY-SA 4.0.