First Battle of the Marne

The First Battle of the Marne was a battle fought in northeastern France from September 6-12, 1914, part of World War I. It was waged between the French and the British Expeditionary Force on the one side, and the armies of the German Empire on the other, chiefly along the Marne river, from which it takes its name. The battle developed as the Franco-British forces attempted to stop the German offensive sweeping through Belgium and into France, aimed at capturing Paris and enveloping the bulk of the French army, in accordance with the Schlieffen Plan, which might then have achieved a quick victory for Germany on the Western Front.

The Battle of the Marne was the bloodiest battle of the war to date on the Western Front, with an estimated 250,000 casualties on each side. It is generally reckoned a victory for the (French and British) Allies, as they successfully halted the German advance toward Paris and thus thwarted the realization of the Schlieffen Plan. The German armies retreated after the battle, and their overall commander, General Helmuth von Moltke, is said to have told his sovereign, Kaiser Wilhelm II, "Your Majesty, we have lost the war." The Allies were unable to follow up their victory by breaking through the German lines, though, and by the end of the year, both sides would have entrenched, beginning the stalemate of trench warfare that would characterize the Western Front for most of the next four years.

Background

Following the assassination of the Austrian archduke Franz Ferdinand in Sarajevo and the subsequent July Crisis, the major powers of Europe went to war at the end of July and the beginning of August, 1914. Germany, facing a two-front war against Russia in the east and France in the west, had long since decided to resolve the situation via the Schlieffen Plan, which called for a rapid invasion of France from the northeast via neutral Belgium to capture the capital city of Paris, encircle and crush the French armies, and thus quickly knock the country out of the war; it could then throw the bulk of its military against Russia.

In accordance with this plan, German armies crossed into Belgium on August 3, an act which brought Great Britain into the war the following day, as it was a guarantor of Belgian neutrality. The French, for their part, had committed most of their forces against their direct border with Germany further south, in a bid to regain Alsace-Lorraine, which they had lost after the Franco-Prussian War of 1870-71. This left them especially at risk of being enveloped from the north and west. However, stiff resistance from the small Belgian army significantly slowed the German advance, giving the Allies time to marshal their resources and regroup. (Out of frustration, German soldiers increasingly resorted to such terror tactics as arson, vandalism, and the shooting of Belgian civilians; this so-called "Rape of Belgium" drew global outrage, turning public opinion in many noncombatant countries--including the United States--against Germany.)

Battle of the Frontiers

Despite the mounting evidence of the Germans' intention to outflank them, the French armies, under the leadership of General Joseph Joffre, for some time continued their eastward offensive into Alsace-Lorraine, with accompanying thrusts northeastward into the Ardennes region. Attacks around Metz and Mulhouse had been decisively stopped by German defenders by August 20, however, and the offensive into the Ardennes was even more bloodily halted. By August 24, the same day on which soldiers of the German 1st Army crossed from Belgium into France, it was recognized at Joffre's headquarters that these attacks, collectively known as the "Battle of the Frontiers," had failed, and that the five French armies were in danger of being cut off from Paris by the larger German offensive. Only the British Expeditionary Force (BEF) under Sir John French, then only about 70,000 strong, and part of the French 5th Army, stood in its way.

The Great Retreat

On August 24, Joffre issued orders canceling the French offensives; instead, the 1st, 2nd, and 3rd Armies were to conduct a fighting retreat westward, while the 4th and 5th (soon joined by a new army, the 6th, formed out of detachments from other units) supported the BEF in blunting the German advance between Lille and Sedan. General Order No. 2, issued the following day, outlined plans for a defensive stance along the Somme river, between Paris and the existing front line. The military governor of Paris, General Joseph Gallieni, made plans for a close-up defense of the capital, though there were relatively few available troops to defend it with. However, the German armies were advancing too rapidly; by the 29th, after heavy losses suffered by the French 5th Army around St. Quentin and the retreat of the BEF from around Compiègne, Joffre was forced to abandon the idea of a stand on the Somme, and ordered a further withdrawal southward, towards the Marne, and entertained the possibility of retreating as far as the Seine river. By September 1, elements of the German First Army, under General Alexander von Kluck, were only thirty miles from Paris, and there was serious talk of evacuating the capital.

Preparations

Despite the impressive German advance--more or less in keeping with the timetable laid out by the Schlieffen Plan--the attackers' situation was more delicate than it appeared. Troops had been detached east to reinforce efforts against the Russians, while others had been committed to the Alsace-Lorraine front due to Moltke's belief that he could achieve a breakthrough around Nancy and then attempt a great double envelopment. As a result, the five German armies advancing through northeastern France were significantly weaker than originally envisioned.

The practical effect of this was that the German line was increasingly thin, with sizable gaps between some of its units. To close up these gaps, and in the belief that the core of the French army was retreating to the southeast, von Kluck had already on August 31 begun angling his First Army that same direction, towards the Marne, rather than swinging west of Paris as earlier planned. However, the Allied forces, though still retreating, were not as disorganized as the German high command assumed, and Kluck faced stiff resistance from the BEF in particular over the next several days. In the process, his right flank became exposed from the direction of Paris, now to his west, where Gallieni was building up the new 6th Army, to which the city's garrison forces were added.

Learning of the changed tactical situation on September 3, Gallieni at once urged Joffre to permit an immediate flank attack upon the Germans, which Joffre personally favored but was unwilling to undertake without the active participation of the BEF. The British and French armies were separate commands, and Sir John French, the BEF's commander, was not only on poor terms with Joffre and his other counterparts, but had become increasingly pessimistic in the past weeks of fighting and seemed to prefer a retreat back to Britain altogether. After receiving what he understood as assurances from BEF headquarters that the British would join in a counterattack, though, Joffre on the evening of the 4th issued orders for an attack by his left wing on September 6. The French 5th and 6th Armies, together with the BEF, would attack Kluck's First Army, now astride the Marne river east of Château-Thierry, with the 3rd and 4th Armies engaging in a frontal attack against the German lines farther east.

French had not, in fact, committed the BEF to Joffre's counterattack, and in fact that same evening indicated his plans to resume his retreat, back toward Fontainebleau. Joffre was forced to travel to French's headquarters at Melun on the 5th, and made a personal appeal to the British general, emphatically protesting, "Monsieur le Maréchal, the honor of England is at stake!" Moved by his words, French reversed himself and promised "we will do all we possibly can." By late afternoon, then, Joffre had achieved the necessary conditions for his planned offensive the following morning.

By this time, Moltke had realized his initial plan had misfired and that the Allies were preparing a large-scale counterattack. Accordingly, he ordered his (westernmost) First and Second Armies to stand on the defensive, while the Third, Fourth, and Fifth stayed on the offensive further east around Verdun to open the way for envelopment of the French right. The same day these orders were issued (September 5th), though, General Hans von Gronau, commanding the IV Reserve Corps that covered Kluck's western flank, received intelligence of the French 6th Army's advance toward his front as part of Joffre's planned offensive, and responded with an immediate attack of his own along the Ourcq, a minor tributary of the Marne. Gronau's corps successfully held the 6th Army at bay until nightfall, after which it fell back; while Kluck, now alerted of the threat to his flank, began to reorient his army to face this new threat.

Main Battle

Battle of the Ourcq

Though Kluck's right wheel had successfully prevented a flank attack by the 6th Army, he had in the process weakened his main front, facing south near the town of Coulommiers, and opened a significant gap (as wide as thirty miles) with neighboring Second Army (under General Karl von Bülow), which in turn was shifting its troops further east, thinning the lines even more. This sector was among those already earmarked for attack by Joffre, who on September 6 sent the 5th Army and the BEF forward against the lines held by Kluck and Bülow. Though the British, who had a longer distance to cover after their earlier retreat, and made a slower march, were delayed in joining the fight, they had by day's end succeeded in crossing the Marne near Rozoy and pushing Kluck's troops back. The French 5th Army, meanwhile, under General Louis Franchet d'Esperey, brought heavy pressure to bear on Bülow's army around the Grand Morin and Petit Morin rivers (for which it is sometimes called "The Battle of the Two Morins").

While Allied progress was less than hoped (for which d'Esperey blamed the British high command), Bülow had taken alarm at the sharp action on his front, and on September 7th began to withdraw behind the Petit Morin, thus widening the gap with Kluck and clearing the way for a mass Allied advance to and across the Marne. For his part, Kluck and the French 6th Army under Michel-Joseph Maunoury had been trading attacks and counterattacks over the past two days, and as more of the German troops were in battle-ready condition, they more generally held the initiative. For a time on the 7th, Kluck's army in fact threatened a breakthrough, but the French lines held, thanks in part to the arrival of reinforcements from the Paris garrison who were transported to the battlefield by the city's taxis: an event memorialized as the taxis de la Marne. Despite these and other reinforcements, as late as the evening of September 8th Kluck believed he could envelop Maunoury's flank and retrieve the broader situation; however, that same day, d'Esperey's 5th Army had resumed its assaults on Bülow's front, leaving the German formations still at risk of being isolated and destroyed piecemeal.