First Battle of the Marne

From September 6 to 12, 1914, French and British armies fought German armies along the Marne river, east of Paris, in the first great battle of World War I on the Western Front. The Germans had invaded Belgium and northern France in August under the Schlieffen Plan, a scheme to sweep around Paris through Belgium and defeat France in about six weeks before turning on Russia. By early September their right wing was only about 40 kilometers from Paris. The French commander, General Joseph Joffre, ordered a counteroffensive instead of a further retreat.¹

The plan had worked less well than designed. The German armies were worn out from marches of up to 30 kilometers a day, their supply lines were stretched, and some forces had been sent east to meet a Russian offensive. The commander of the First Army, Alexander von Kluck, turned southeast, passing east of Paris and exposing his flank to a new French Sixth Army under Michel-Joseph Maunoury. The Paris military governor, Joseph Gallieni, sent troops to the front, including soldiers carried in about 600 requisitioned Paris taxis on the night of September 7 and 8. A gap opened between the German First and Second Armies, and the British Expeditionary Force and the French Fifth Army moved toward it.¹²

After the staff officer Lieutenant Colonel Richard Hentsch visited the front and approved a withdrawal, the Germans retreated to the Aisne river and dug in. Both sides lost hundreds of thousands of men. Over the following weeks the armies tried to outflank each other in the Race to the Sea, and by late 1914 a continuous line of trenches ran from the Swiss border to the North Sea. The war of movement was over, and a war of attrition began that would last until 1918.¹