Aftermath of the First Battle of the Marne

Introduction, Contents, and Sources

At the outbreak of war in August 1914, the European powers put their faith in detailed war plans.  The German Schlieffen Plan and the French Plan 17 both called for immediate full-scale offensives, but both were seriously flawed.  The French weren’t strong enough to have a reasonable hope of decisively defeating Germany at the outset.  The German strategy was somewhat more realistic, envisioning a massive offensive that would wheel through the neutral Low Countries, crush the French left wing, and roll up the remaining French armies.  But if the French could evade complete defeat in the first clash at the borders, the Germans would only be indecisively pushing them back while exposing their own open flank to a French counterattack.  If the Schlieffen Plan didn’t work at the very beginning, it quite likely wouldn’t work at all… and if it didn’t work it would be disastrous for Germany, since the invasion of Belgium would very probably bring Britain into the war on the side of France, entangling Germany in an exhausting and prolonged war.

Both sides ignored anything that cast doubt on their chosen strategies.

And no one really knew what the war would be like.  There had not been a general European war for ninety-nine years; there had not been any wars between European powers for almost half a century.  Professional soldiers were well aware that weaponry had been revolutionized in that time, and that armies had vastly increased their firepower, but they weren’t sure what effect this would have on the battlefield or what tactics they should adopt.  They would find out the hard way.

As soon as the armies marched over the borders, they began to collide with reality.  Belgium was the first surprise, resisting the German invasion with unexpected determination at Liège, and inflicting a small but important delay on the Schlieffen Plan.

The real shock came on Aug.20-24, when the main bodies of the opposing armies plowed into each other in a series of spasmodic clashes known as the Battles of the Frontiers.  Everywhere, the Germans won.  The French initially used hopelessly outmoded tactics and suffered astronomical losses; the British were more effective, but were too few in number.  These first battles were the Germans’ best chance of a really decisive victory, all the more so since the French commander Joffre stubbornly refused to abandon Plan 17 and withdraw his armies.  Fortunately for the Allies, his subordinates did what they needed to do to save their troops and began to pull back with or without orders, beginning a long retreat.

The armies trudged southwards into France, periodically colliding in local battles, pushing themselves to exhaustion and beyond.  The strain of this grueling march caused many commanders on both sides to loose their grip, but Joffre rose to the occasion, keeping cool throughout the crisis and actively maintaining control of his armies.

By early September, he and some of his subordinates saw a chance for a counterstroke.  In the First Battle of the Marne on Sep.05-10, the Allies finally stopped the German invasion, but the victory was even less decisive than the Battle of the Frontiers.  The Germans simply withdrew a few miles north to the Aisne River and dug in.  This was the first section of the trench system that within a few months would immobilize the Western Front until 1918.


(1)  Background, to Aug.02.1914

(2)  The Opening Moves on the Western Front, Aug.03-19

(3)  The Battles of the Frontiers, Aug.20-24

(4)  The Long Allied Retreat, Aug.25-Sep.04

(5)  The First Battle of the Marne and its Aftermath, Sep.05-15

Biographies and Glossary

Sources for this section include (websites in parentheses):
Robert B. Asprey.  The First Battle of the Marne.  1962
Correlli Barnett.  The Swordbearers: Supreme Command in the First World War.  1963 
(Battle of Liege)
Trevor N. Dupuy.  Harper Encyclopedia of Military History, 4th Edition.  1993 
Trevor N. Dupuy, et al.  The Harper Encyclopedia of Military Biography.  1992
David Eggenberger.  An Encyclopedia of Battles.  1967, 1985
Ferdinand Foch.  The Memoirs of Marshal Foch.  1931
Edward Gleichen, ed.  Chronology of the Great War.  1918-20/1988
Randal Gray.  Chronicle of the First World War, 2 vols.  1990
John Keegan.  August 1914: Opening Moves.  1971
Lyn MacDonald.  1914: The First Months of Fighting.  1988
Stephen Pope & Elizabeth-Anne Wheal.  The Dictionary of the First World War.  1995
Edward Spears.  Liaison 1914: A Narrative of the Great Retreat.  1930/1968
John Terraine.  Ordeal of Victory.  (biography of Douglas Haig)  1963
John Terraine.  Mons.  1960.
Barbara Tuchman.  The Guns of August.  1962