The 50 skeletons were probably French soldiers who died during a battle near Alerheim on August 3, 1645, the Bavarian State Office for Historical Preservation (BlfD) said on Monday in Munich.
French-Hessian-Weimar troops led by Prince Condé are believed to have confronted the Bavarian army led by General Franz Freiherr von Mercy on that day.
French coins, rosaries and bits of uniforms were also found in the mass grave. The site is the second known archaeologically documented mass grave from this time period. Another grave from 1636 was discovered last year in Wittstock in the German state of Brandenburg.