On this day in World War I, the French attack advancing Germans northeast of Paris, and the Battle of the Marne begins. After the outbreak of hostilities in Europe in August 1914, Germany took the offensive in the West, hoping to defeat France before the Russians made too many advances in the East. The Germans rushed across Belgium, routing the Allies, and by September the Schlieffen Plan–the planned outflanking of the French forces–seemed headed to a triumphant conclusion. German forces crossed the Marne River to the northeast of Paris, and the French government was evacuated. However, on September 5, 1914, the French began attacking the Germans’ exposed right flank, and by the next day the counterattack was total. On September 9, the exhausted Germans began their retreat, and Paris was saved. An estimated 500,000 men were killed or wounded in the Battle of the Marne.