Holding the Line: First Battle of the Marne

First Battle of the Marne - Conflict & Dates:

The First Battle of the Marne was fought September 6-12, 1914, during World War I (1914-1918).

Armies & Commanders

Germany

Chief of Staff Helmuth von Moltke
approx. 1,485,000 men (August)

Allies

First Battle of the Marne - Background:

With the outbreak of World War I, Germany began implementation of the Schlieffen Plan.

This called for the bulk of their forces to assemble in the west while only a small holding force remained in the east. The goal of the plan was to quickly defeat France before the Russians could fully mobilize their forces. With France defeated, Germany would be free to focus their attention to the east. Devised earlier, the plan was altered slightly in 1906 by Chief of the General Staff, Helmuth von Moltke, who weakened the critical right wing to reinforce Alsace, Lorraine, and the Eastern Front (Map).

With the outbreak of World War I, the Germans implemented the plan which called for violating the neutrality of Luxembourg and Belgium in order to strike France from the north (Map). Pushing through Belgium, the Germans were slowed by stubborn resistance which allowed the French and arriving British Expeditionary Force to form a defensive line. Driving south, the Germans inflicted defeats on the Allies along the Sambre at the Battles of Charleroi and Mons.

Fighting a series of holding actions, French forces, led by commander-in-chief General Joseph Joffre, fell back to a new position behind the Marne with the goal of holding Paris.

Angered by the French proclivity for retreating without informing him, the commander of the BEF, Field Marshal Sir John French, wished to pull the BEF back towards the coast, but was convinced to stay at the front by War Secretary Horatio H. Kitchener. On the other side, the Schlieffen Plan continued to proceed, however Moltke was increasingly losing control of his forces, most notably the key First and Second Armies.

Commanded by Generals Alexander von Kluck and Karl von Bülow respectively, these armies formed the extreme right wing of the German advance and were tasked with sweeping to the west of Paris to encircle Allied forces. Instead, seeking to immediately envelop the retreating French forces, Kluck and Bülow wheeled their armies to the southeast to pass to the east of Paris. In doing so, they exposed the right flank of the German advance to attack. Becoming aware of this tactical error on September 3, Joffre began making plans for a counter-offensive the next day.

Moving to Battle:

To aid this effort, Joffre was able to bring General Michel-Joseph Maunoury's newly-formed Sixth Army into line northeast of Paris and to the west of the BEF. Using these two forces, he planned to attack on September 6. On September 5, Kluck learned of the approaching enemy and began to wheel his First Army west to meet the threat posed by Sixth Army. In the resulting Battle of the Ourcq, Kluck's men were able to put the French on the defensive. While the fighting prevented the Sixth Army from attacking the next day, it did open a 30-mile gap between the First and Second German Armies (Map).

The First Battle of the Marne:

Utilizing the new technology of aviation, Allied reconnaissance planes quickly spotted this gap and reported it to Joffre. Quickly moving to exploit the opportunity, Joffre ordered General Franchet d'Espérey's French Fifth Army and the BEF into the gap. As these forces moved to isolate the German First Army, Kluck continued his attacks against Maunoury. Composed largely of reserve divisions, the Sixth Army came close to breaking but was reinforced by troops brought from Paris by taxicab on September 7. On September 8, the aggressive d'Espérey launched a large-scale attack on Bülow's Second Army driving it back (Map).

By the next day, both the German First and Second Armies were being threatened with encirclement and destruction. Told of the threat, Moltke suffered a nervous breakdown. Later that day, the first orders were issued for a retreat effectively negating the Schlieffen Plan. Recovering, Moltke directed his forces across the front to fall back to a defensive position behind the Aisne River. A wide river, he stipulated that "the lines so reached will be fortified and defended." Between September 9 and 13, German forces broke off contact with the enemy and retreated north to this new line.

Aftermath of the Marne:

Allied casualties in the fighting numbered around 263,000, while the Germans incurred similar losses. In the wake of the battle, Moltke reportedly informed Kaiser Wilhelm II, "Your Majesty, we have lost the war." For his failure, he was replaced as Chief of the General Staff on September 14 by Erich von Falkenhayn. A key strategic victory for the Allies, the First Battle of the Marne effectively ended German hopes for a quick victory in the west and condemned them to a costly two-front war. Reaching the Aisne, the Germans halted and occupied the high ground north of the river.

Pursued by the British and French, they defeated Allied attacks against this new position. On September 14, it was clear that neither side would be able to dislodge the other and the armies began entrenching. At first these were simple, shallow pits, but quickly they became deeper, more elaborate trenches. With the war stalled along the Aisne in Champagne, both armies began efforts to turn the other's flank in the west. This resulted in a race north to the coast with each side seeking to turn the other's flank. Neither was successful and by the end of October a solid line of trenches ran from the coast to the Swiss frontier.