The war began as expected, with opposing armies moving rapidly against each other and maneuvering for advantage.
The Germans swept through neutral Belgium to crash into northern France, as part of a long-prepared strategy called the 'Schlieffen Plan.' The French moved east to recapture Alsace and Lorraine.
Britain met its obligations to France and Belgium by pouring troops into the path of advancing German forces in Flanders, along the border between France and Belgium near the English Channel.
Austrian forces struck Serbia, Russia moved against eastern Germany, and Russian and Austro-Hungarian forces clashed in central Europe.
Near Defeat for France and Britain
The war in the west was almost lost. The German armies swept south, while French forces were stopped, with heavy casualties, in their eastward offensive. But after German forces had marched several hundred kilometres towards Paris, a combined French and British force halted them in the five-day Battle of the Marne in early September. The exhausted Germans reeled back to establish firmer defensive positions. The battle saved France, but a large swath of territory had been lost, and many tens of thousands killed.
The Race to the Sea
Following the Battle of the Marne, German and Allied armies maneuvered against each other, seeking an open flank to slip past and force the other's retreat.
In a series of battles known collectively as the 'Race to the Sea,' each side defeated the other's efforts to outflank it. The fighting front from Paris to the English Channel then filled in with opposing defence lines, as the withering effects of firepower forced soldiers to dig into, and under, the ground.
Within a few months, and after hundreds of thousands of casualties, all movement had ceased. Armies faced one another across an enormous trench system that stretched some 700 kilometers from Switzerland to the North Sea. Frontal assaults against artillery, machine-guns, and massed rifle fire caused terrible casualties.
The quick war in the West had ground to a stalemate and would now enter a static phase broken rarely over the next four years. In some places, especially on the vast Eastern Front or in the deserts of the Middle East, armies retained greater mobility, but in western Europe, northern Italy, the Balkans, and anywhere else that firepower could dominate movement, the troops dug in and trench warfare began.
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