France very nearly failed to repulse Germany’s mammoth initial invasion. But it did, leading to a slaughterous long-term war of attrition.

The Battle of the Marne was a close-run thing. It confirmed the elder Helmuth von Moltke’s famous counsel that no plan of operations “survives with certainty beyond the first encounter with the enemy’s major forces.” And it reaffirmed Carl von Clausewitz’s dictum that “war is the realm of uncertainty; three quarters of the factors on which action in war is based are wrapped in a fog of greater or lesser uncertainty.” Nothing about the battle was preordained; choice, chance, and contingency lurked at every corner. Relatively minor changes in events and choices during that titanic and bloody clash of arms might have ruled out World War II, preserved three great European empires, and made America’s transition to superpower status highly unlikely.

But senior commanders on both sides did not at first understand the magnitude of the decision at the Marne. It seemed simply a small blip on the way to victory. The armies would be rested, reinforced, resupplied, and soon again be on their way either to Berlin or to Paris. Below headquarters and army levels as well as at corps commands, a million men on either side likewise had no inkling of what “the Marne” meant—except more endless marches, more baffling confusion, and more bloody slaughter. Future historian Marc Bloch, a sergeant with the French 272nd Infantry Regiment, on September 9 recalled marching down a “tortuously winding road” near Larzicourt on the Marne at night, oblivious to the fact that the great German assault had been blunted. “With anger in my heart, feeling the weight of the rifle I had never fired, and hearing the faltering footsteps of our half-sleeping men echo on the ground,” he drearily noted, “I could only consider myself one more among the inglorious vanquished who had never shed their blood in combat.”

The Battle of the Marne did not end World War I. But if “strategically and operationally” it was “tactically indecisive,” in the words of historian Hew Strachan, it was also a “truly decisive battle in the Napoleonic sense.” Germany had failed to achieve the victory promised in the younger Moltke’s deployment of the Schlieffen Plan. Kaiser Wilhelm II now faced a two-front war of incalculable duration against overwhelming odds. A new school of German military historians goes so far as to suggest that Germany had lost the Great War by September 1914.

Still, “what if” scenarios abound. What if Germany had not violated Belgium’s neutrality? Would Britain still have entered the war? What if German Chief of the General Staff von Moltke had not sought a double envelopment of the enemy in AlsaceLorraine and in northern France? Could at least half of the 331,000 soldiers on the left wing have helped the right wing to victory? What if he had not sent III and IX army corps to the east? Could one of those have filled the famous gap that developed between Second and First armies on the Marne? What if the counterattacking French had better exploited that gap? And what if the German Third Army had been reinforced to break the French Ninth Army’s fragile front at the Saint-Gond Marshes?

What if the commanders of Germany’s First and Second armies had simply refused to follow Lt. Col. Richard Hentsch’s “recommendation” to retreat from the Marne? Could those armies have held on the Ourcq and Marne rivers, with possibly war-ending results?

What if Joseph Joffre had not been the French commander in chief? What if he had been cashiered in late August after he had been soundly defeated in the Battle of the Frontiers and after his deployment plan had totally collapsed? What historian Sewell Tyng called Joffre’s “inscrutable, inarticulate calm,” his “placid, unsophisticated character,” and his “far-sighted, unsentimental, determined” leadership were among the major reasons the French did not repeat their collapse of 1870–1871.

Immediately after losing the Battle of the Frontiers, Joffre had recognized that “the game had been poorly played.” He had broken off the campaign with every intention of resuming it as soon as he had “repaired the weaknesses discovered.” Once clear on the enemy’s ultimate intention to march across Belgium, Joffre had shifted forces from his right wing to his left, had cashiered general officers he found to be “not up to standard,” had orchestrated an orderly withdrawal behind the Marne and Seine rivers, had created General Michel-Joseph Maunoury’s new “army of maneuver” in the west, and had launched his great attack between “the horns of Paris and Verdun” when he deemed the moment favorable.

After the war, Marshal Ferdinand Foch paid General Joffre due tribute. “When this moment arrived, he judiciously combined the offensive with the defensive after ordering an energetic about-face,” Foch said. “By a magnificently planned stroke, he dealt the invasion a mortal blow.” He believed Joffre’s performance compared to the lethargic, doubting, distant, “physically and mentally broken” younger Moltke determined much of the outcome.

What if French morale had cracked after the Battle of the Frontiers? Campaigns are not fought against lifeless bodies. The enemy reacts, innovates, surprises, and strikes back. Were it not for the emotions and passions of the troops, Clausewitz reminds us, wars would not escalate and might not even have to be fought.

Comparative figures of opposing strengths will not suffice to decide the issue without also taking into account the physical impact of the fighting forces. Put differently, a kind of war by algebra was undermined by fighting spirit. In 1914, the French poilu surprised the Germans with what Moltke referred to as élan. “Just when it is on the point of being extinguished,” he wrote his wife at the height of the Battle of the Marne, it “flames up mightily.”

Karl von Wenninger, the Bavarian military plenipotentiary at Imperial Headquarters, likewise expressed his surprise at the enemy’s tenacity. “Who would have expected of the French,” he wrote his father on September 9, “that after ten days of luckless battles a[nd] bolting in open flight they would attack for three days so desperately.”

Gen. Alexander von Kluck, who commanded the German First Army, gave the adversary his full respect in 1918. “The reason that transcends all others,” he informed a journalist, in explaining Germany’s failure at the Marne, was “the extraordinary and peculiar aptitude of the French soldier to recover quickly.” Most soldiers “will let themselves be killed where they stand”; that, after all, was a given in all battle plans. “But that men who have retreated for ten days…that men who slept on the ground half dead with fatigue, should have the strength to take up their rifles and attack when the bugle sounds, that is a thing upon which we never counted; that is a possibility that we never spoke about in our war academies.”

Perhaps the greatest “what if” scenario: What if Kluck’s First Army had indeed turned the left flank of Maunoury’s Sixth Army northeast of Paris, instead of veering south to prevent opening a gap with the Second Army and stopping 13 miles short of the capital? For most German military writers and the German official history of the war, Der Weltkrieg 1914 bis 1918, this was a “certainty.” Victory assured. End game. War over.

But Moltke’s chief of operations, Lt. Col. Gerhard Tappen, stated after the war that he was not so sure. He, the Gabriel ever trumpeting victory throughout August and early September 1914, conceded that even General Kluck’s triumph at the Ourcq River would not have been decisive to the overall war effort. Given the dogged tenacity of the British and their “well-known war aims,” he felt the war would have dragged on even had Paris fallen.

Even if, thereafter, First Army had pivoted on its left and squared off with the three army corps of the British Expeditionary Force and Louis Conneau’s cavalry corps, Tappen thought the result likely would have been utter exhaustion for the armies on both sides, ending in stalemate. And yet, in this honest appraisal from one not known for candor, Tappen wondered, did not Kluck owe it to his troops and the nation to fight the battle through to its conclusion?

The campaign in the west in 1914 revealed two distinct command styles. Moltke was content to remain at Army Supreme Command headquarters, far removed from the front—first in Koblenz and then in Luxembourg—and to give his field commanders great latitude in interpreting his general directives. He chose not to closely control them by telephones, automobiles, aircraft, or general staff officers. After all, they had conducted the great annual prewar maneuvers and war games and, having done so, could be counted on to execute his thoughts. Already, in peacetime, Moltke had let it be known that it sufficed for commanding generals simply to be “informed about the intentions of the High Command,” and that this could easily be accomplished “orally, through the sending of an officer from the Headquarters.” The reality of war proved otherwise.

Some commanders failed the ultimate test—war—mainly because of incompetence (Max von Hausen); some partly because of advanced age (Karl von Bülow); and others partly because of ill health (the elder Helmuth von Moltke, Otto von Lauenstein). General Moriz von Lyncker, chief of the military cabinet, struck at the heart of the matter on September 13. “It is clear that during the advance into France the necessary tight leadership on the part of the Chief of the General Staff had been totally lacking.” The next day he convinced Kaiser Wilhelm to place Moltke on sick leave.

But while more than 30 German generals were relieved of command of troops in 1914, there was no general “housecleaning” at the very top. Three army commanders were beyond reach, of course, because they were in line for future crowns: Wilhelm of Prussia led Fifth Army until August 1916, when he took command of Army Group Deutscher Kronprinz for the rest of the war; Rupprecht of Bavaria headed Sixth Army until August 1916, when he was given charge of Army Group Kronprinz Rupprecht until November 1918. And Albrecht of Württemberg stayed with Fourth Army until February 1917, when he assumed command of Army Group Herzog Albrecht for the duration.

Not even the two most controversial army commanders were sacked after the Battle of the Marne. Karl von Bülow, who had shown less than boldness first at the Sambre and then at the Marne, not only was promoted to the rank of field marshal in January 1915 and awarded Prussia’s highest military order, the Orden Pour le Mérite, but was rewarded for his mediocre performance by (again) being given command of the First Army and then of the Seventh Army as well. He led the Second Army until April 1915, when he was temporarily relieved of command after a stroke. He was forced to retire two months later; his pleas to be reinstated fell on deaf ears.

Alexander von Kluck, who had disobeyed Moltke’s orders and turned in southeast of Paris, commanded First Army until March 1915, when near Vailly-sur-Aisne he was severely injured in the leg by shrapnel. He turned 70 while recuperating and in October 1916 was retired. Max von Hausen was the only army commander relieved of duty, and that was mainly because he had a severe case of typhus. His desperate appeals to be reinstated also went unanswered.

After the Battle of the Marne, the German army of 1914 was gone forever. Its tidy division into federalist Baden, Bavarian, Prussian, Saxon, and Württemberg contingents ended, never to be revived. In the words of former Prussian war minister Karl von Einem, the new commander of the Third Army, “The army totally loses its wartime separateness. Everything is moved about, divisions and brigades are thrown together. It is living from hand to mouth.” In short, a true “German” army fought the Great War for the next four years.

Joseph Joffre, in contrast to Moltke, played a highly active, indeed intense, role in French decision-making. Apart from issuing a host of general instructions, special instructions, and special orders, he showered army commanders with hundreds of “personal and secret” memoranda, telephone calls, and individual orders. He used his driver and automobile to great advantage, being constantly on the road to inspect, to order, to encourage and, where necessary, to relieve.

In fact, after the Marne, Joffre filled a park with so-called limogés. These were ineffective commanders he “retired” to Limoges, 250 miles southwest of the nerve center of Paris. They included, by his reckoning, two army commanders, 10 corps chiefs, and 38 division heads. Some (Charles Lanrezac) he fired because he considered them to be overly pessimistic or too willing to challenge his orders; others (Pierre Ruffey) because he found them to be unnecessarily nervous and imprudent in their dealings with subordinates. He maintained in command a core of loyal and aggressive army commanders (Fernand de Langle de Cary, Yvon Dubail, Édouard de Castelnau), and he promoted several corps commanders (Louis Franchet d’Espèrey, Ferdinand Foch, and Maurice Sarrail) because they had “faith in their success,” and who by “mastery of themselves” knew how to “impose their will on their subordinates and dominate events.” He never regretted his sometimes-unjustified firings. After the war, he declined to engage the “victims” in a war of memoirs.

Ironically, given the elder Moltke’s strategic use of railways against Austria-Hungary in 1866 and again against France in 1870–1871, it was Joffre who in 1914 brilliantly used his directorate of railways and interior lines to great advantage. When by August 24 he realized that he had lost the Battle of the Frontiers, that his concentration plan lay in tatters, and that the Germans were indeed sweeping through Belgium, Joffre altered the center of gravity of his dispositions so as to achieve at last a substantial numerical superiority at the western extremity of the front, which he had come to recognize as the decisive point. As early as August 26, he dissolved the ineffective Army of Alsace, reconstituted much of it as Frédéric Vautier’s VII Corps, and then sent it to reinforce the Entrenched Camp of Paris.

Two days later, as the Battle of the Trouée de Charmes wound down, Joffre dispatched Georges Levillain’s 6th Cavalry Division and Louis Comby’s 37th Infantry Division to the capital. And then he orchestrated a staggering transfer of forces from Lorraine to Greater Paris between August 31 and September 2: from First Army, Edmond Legrand-Girarde’s XXI Corps; from Second Army, Louis Espinasse’s XV Corps, Pierre Dubois’s IX Corps, Justinien Lefèvre’s 18th Infantry Division, and Camille Grellet de la Deyte’s 10th Cavalry Division; and finally, from Third Army, Victor Boëlle’s IV Corps. The younger Moltke, by contrast, eschewed major transfers of forces from his left to his right wing because of technical difficulties and downright stodginess.

The carnage was frightful. Although the French army published no formal casualty lists, its official history, Les Armées Françaises dans la Grande Guerre, set losses for August at 206,515 men and for September at 213,445; losses for the 10 days at the Marne surely must have approached 40 percent of the latter figure. The chapel of the École Spéciale Militaire de Saint-Cyr, before its destruction in World War II, had only a single entry for its dead in the first year of the war: “The Class of 1914.” In terms of natural resources and industrial production, France had lost territory from which 64 percent of its iron, 62 percent of its steel, and 50 percent of its coal had originated before the war. The German army likewise published no official figures for the Marne. But according to its 10-day casualty reports, the armies in the west sustained 99,079 casualties between September 1 and 10. Unsurprisingly, the army corps that took the brunt of the fighting during that 10-day period suffered most heavily: Hans von Gronau’s IV Reserve Corps with First Army (2,676 killed or missing and 1,534 wounded); Otto von Emmich’s X Corps with Second Army (1,553 killed or missing and 2,688 wounded); and Maximilian von Laffert’s XIX Corps with the Saxon Third Army (2,197 killed or missing and 2,982 wounded). Taking together all five German armies between Verdun and Paris, roughly 67,700 Landser were rendered hors de combat in the Battle of the Marne. Total British casualties at the Marne were 1,701.

Horses died in equally horrid numbers. For the first year of the war, no one bothered to keep records: The historians of the Reichsarchiv at Potsdam in the 1920s could not find the files of a single cavalry division with regard to “sickness or loss of horses.” Only the 22nd Infantry Division kept tabs from the start of the war in Belgium, and it reported a loss of roughly 30 percent. Most were not from combat but from exhaustion, colic, saddle sores, lung disease, withers fistulas, and improper shoeing. Since no veterinary clinics existed yet, sick or wounded animals were simply shot in the field—and thus escaped official records. During World War I, Germany lost an estimated one million horses dead and seven million wounded.

Artillery ruled the battlefield. The German 105mm and 150mm howitzers, called “cooking pots” (marmites British, and the lighter 77mm guns ripped men and ) by the French and “Jack Johnsons” by the horses alike into shreds of flesh and deposited their remains as mounds of pulp. The French 75s, dubbed “black butchers” by the Germans, filled the air with shrieking shrapnel shells (rafales) that exploded above the enemy and drenched those below with thousands of iron balls.

For four weeks after the Marne fighting, “crude, stinking, crowded ambulance wagons” jostled the wounded back to barns and churches hastily converted into field hospitals, where the unfortunates lay for hours “in a cloud of flies drinking [their] blood.” For days, in words historian Robert Asprey addressed to the common soldier of 1914, “you ate nothing, drank nothing, no one washed you, your bandages went unchanged, many of you died.”

The murderous nature of industrialized warfare changed the common soldiers as they conducted it. Regardless of social, regional, or religious origin, they wrote home of the filth and dirt, horror and fear of their front-line experiences. Some remembered the initial euphoria of marching through fall-clad orchards, the camaraderie among soldiers, the welcome mail calls, the “playing at cowboys and Indians” while advancing through woods, and the “liberating” of wonderful wine cellars. Most remembered the constant, nagging hunger and thirst, the endless marches by day and night, the choking dust, the searing heat, then the cold rain and oozing mud, the burning villages, the groaning of the wounded, and the death rattles of the dying.

An anonymous German soldier wrote to the miner’s newspaper, Bergarbeiter-Zeitung, in Bochum just after the Marne: “My opinion about the war itself has remained the same: it is murder and slaughter, and it is still incomprehensible to me today that humankind in the twentieth century could commit such slaughter.” A university professor expressed his opinion on the war in more prosaic terms. “I have seen so much that is grand, beautiful, monstrous, base, brutal, heinous, and gruesome, that like all the others I am totally stupefied. To see people die hardly interrupts the enjoyment of the coffee that one has triumphantly brewed in stark filth while under artillery fire.”

A French poilu, the future renowned violoncellist Maurice Maréchal, expressed much the same disillusion in early September. His initial “beautiful, innocent joy” at the call of “Victory! Victory!” at the Marne quickly “took flight” as he surveyed the battlefield: “There, a lieutenant of the 74th [Infantry Regiment], there, a captain of the 129th, all in groups of three or four, sometime singly and still in the position of firing prone, red pants. These are ours, these are our brothers, this is our blood…. Oh! Horrible people who wanted this war, there is no torment enough for you!”

Three weeks later, Maréchal reflected again on the war. “Oh, this is long and monotonous and depressing.” The “energy” and the “heroism” of 1870–1871 were absent on the Western Front in 1914. “The heroism of today: hide as best as possible.” Only the carnage was the same. “We feel small, so small, in the face of this frightening thing, some with bloody arms, others with boots ripped to shreds by red holes.” The meaning of the war escaped him. “We do not know, not really, if we have done anything of use for the country.”

The newly promoted Adjutant Bloch of the French 272nd Infantry Regiment had overcome his “war euphoria” of August by year’s end. “I led a life as different as possible from my ordinary existence: a life at once barbarous, violent, often colorful, also often a dreary monotony combined with bits of comedy and moments of grim tragedy.” Thereafter, he experienced primarily the “dreary monotony” of what he called the “age of mud”: constant downpours, caved-in trenches, and unrelieved dampness. “Our clothing was completely soaked for days on end. Our feet were chilled. The sticky clay clung to our shoes, our clothing, our underwear, our skin; it spoiled our food, threatened to plug the barrels of our rifles and to jam their breeches.” Typhoid fever, contracted in the damp netherworld of the trenches, came almost as a relief to him in January 1915.

Above all, the Battle of the Marne destroyed any romantic notions of war. “Wish it were a fresh and jolly tussle,” a German student wrote his parents from the Argonne Forest, “rather than this malicious, gruesome mass assassination.” Mines, hand grenades, and flamethrowers had reduced warfare to a new form of barbarism. “Is such a manner of warfare still compatible with human dignity?” he rhetorically asked his parents.

Yet, despite the savage nature of warfare in the west, morale held. There were no widespread refusals to obey the call-ups in August 1914. Large numbers of volunteers (even if grossly exaggerated for public consumption) rushed to the recruiting depots; and no major rebellions or strikes took place either at home or at the front. None of the armies kept statistics on the killing of officers by their men, or on desertions.

Wherever casualties were broken down under the headings of “cause,” possible deserters were lumped into the generic category of “missing,” which likely referred primarily to prisoners of war. Statistics for the seven German armies in the west show 21 suicides for August and a mere 6 for September 1914. The highest incidence was in Bavarian Sixth Army, with 8 suicides (among 228,680 soldiers). Alcohol and fear of not being up to the task that lay ahead figured in most cases; almost all involved guns. And if one considers that Germany in 1914 suffered 800,000 casualties (including 18,000 officers), then the 251 suicides (19 officers) for that period are statistically insignificant and further proof of the inner steadfastness of those forces.

The Battle of the Marne did not, of course, dictate another four years of murderous warfare. If anything, it prefigured the resilience of European militaries and societies to endure horrendous sacrifices.

Some historians have suggested that Chancellor Theobald von Bethmann Hollweg’s infamous September 9 “war aims program” demanded German domination of Central Europe “for all imaginable time.” Its goals included annexation of Luxembourg, reduction of France and Russia to second-rate powers, “vassal” status for Belgium and Holland, and a German colonial empire in Central Africa. Published at the very height of the struggle at the Marne, it committed Germany to push on to victory regardless of the cost.

But there were those at Imperial Headquarters who fully understood that the time had come in the fall of 1914 to end the Great Folly. Field Marshal Gottlieb von Häseler, activated for field duty at age 78, advised Wilhelm II to sheath the sword: “It seems to me that the moment has come when we must try to end the war.” The kaiser rejected his advice.

Moltke’s successor, Erich von Falkenhayn, by November 19 had reached the same conclusion as Häseler before him. Victory lay beyond reach. It would be “impossible,” he lectured Bethmann Hollweg, to “beat” the Allied armies “to such a point where we can come to a decent peace.” By continuing the war, Germany “would run the danger of slowly exhausting ourselves.” The chancellor rejected the counsel.

It began at the Marne in 1914. It ended at Versailles in 1919. In between, about 60 million young men had been mobilized, 10 million killed, and 20 million wounded. With the 20/20 vision of hindsight, the tragedy of the Marne is that it was strategically indecisive. Had the German First Army destroyed the French Sixth Army east of Paris; had the French Fifth Army and the British Expeditionary Force driven through the gap between German First and Second armies expeditiously; had the French Fifth Army pursued the German Second Army more energetically beyond the Marne; then perhaps the world would have been spared the greater catastrophe that was to follow in 1939–1945.


Adapted from The Marne, 1914 by Holger H. Herwig, ©2009, published by arrangement with Random House Inc.

Originally published in the Spring 2010 issue of Military History Quarterly. To subscribe, click here