Battle of Mars-la-Tour

Battle context

At Mars-la-Tour on 16 August 1870, a single Prussian corps—later reinforced by two more—encountered the full French Army of the Rhine under Bazaine in a meeting engagement. Despite rough parity in final force sizes and heavier Prussian casualties, the engagement ended with the French Army of the Rhine withdrawing toward the fortress of Metz rather than continuing westward. That retreat proved strategically decisive within the Franco-Prussian War: by falling back on Metz, Bazaine's army effectively allowed itself to be encircled, removing the bulk of France's principal field force from offensive operations. The battle thus set the conditions for the subsequent investment of Metz and, together with the later disaster at Sedan, the collapse of organized French resistance in the opening phase of the war.