France and Britain won the First Battle of the Marne between 5 and 12 September 1914, halting the German advance some 50 km (30 miles) from Paris and throwing it back. The victory saved the capital, wrecked Germany's plan for a swift war, and condemned Europe to four years in the trenches; the French remember it as the Miracle of the Marne.
In the first days of September 1914, German armies were barely 50 km (30 miles) from Paris and moving fast. Then, along the river Marne, a French and British counterattack stopped them cold. The victory saved the capital, wrecked Germany's plan for a swift war, and condemned Europe to four years in the trenches. The French remember it as the Miracle of the Marne.
The plan and the gap
Germany's Schlieffen Plan aimed to knock out France in weeks by wheeling through Belgium and around Paris. But the German armies outran their supplies1, and General von Kluck turned his First Army inward too soon2, exposing a flank. A gap opened between the German First and Second Armies3, and Allied scouts, on horseback and in the air, found it.
The taxis of the Marne
The French commander Joffre stayed calm as his armies retreated, then chose his moment to turn and fight. To rush reserves from Paris to the front, the city's military governor Gallieni commandeered around 600 Paris taxicabs4, a small effort in numbers but an unforgettable symbol4 of a nation improvising to survive.
Into the gap
The French Sixth Army struck the exposed German flank5 while the small British Expeditionary Force pushed into the gap between the two German armies. Fearing encirclement, the German command ordered a general retreat to the river Aisne3, where the exhausted armies dug in.
What the day decided
Those trenches never really emptied. From the Aisne the two sides raced north to the sea, extending their lines until a continuous front ran from the Channel to Switzerland2. The war of movement was over.5 Everything that followed, Verdun, the Somme and the rest, grew from the deadlock the Marne began.
The two-front war Germany feared
Germany had gone to war with a single great gamble: knock France out in six weeks3, then turn the full army east against Russia before it could fully mobilise. The Marne destroyed that plan. When the German advance was halted short of Paris and thrown back to the Aisne, the quick victory in the west evaporated, and Germany was left fighting the long war on two fronts that its whole strategy had been designed to avoid. The front lines that formed after the battle would barely move for over three years. What began as a war of sweeping movement froze into the trenches, and a conflict meant to be over by Christmas settled into more than four years of attrition. That first winter, along parts of the line, the shooting briefly stopped for the Christmas truce of 1914.
