World War I raged over four years, from 1914 to 1918, and involved much of Europe. It also spread to the European colonies and non-European powers also intervened (Turkey in favor of Germany and the United States in support of the British and French). The two opposing sides started from an initial inequality: the Triple Entente had more population and resources, and its armies were larger, but Germany and Austro-Hungary had greater technical and organizational capacity, with which they compensated for their initial disadvantage. The war had several phases.
1. Movement warfare
At first, the Germans opt for a «blitzkrieg» or movement warfare, according to General Schlieffen’s plan. The Schlieffen plan wanted to avoid the existence of two combat fronts (one in the west, with France, and another in the east with Russia). To do this, it was necessary to launch quickly on the French front, for once France was defeated, focus on the Russian front, where there were greater difficulties.
However, the Germans did not achieve their objective and France resisted the German attack thanks to the rapid support of Great Britain to the French and the strong resistance of the French army, which at the Battle of the Marne stopped the rapid German advance and prevented the fall of Paris. . Meanwhile, on the eastern front, the Germans soon achieved important successes over Russia, which they defeat in the battles of Tannenberg and Masurian Lakes. Despite everything, Germany had failed in its attempt to eliminate the war on two fronts. From then on he would have to fight in the west with France and Great Britain and in the east with Russia, his army remaining divided in two.
2. Trench warfare
After the failure of the war of movements, the fronts stabilize and a situation of technical tie between the contenders is reached. The balance is total. The battle fronts barely moved for years, developing a war of wear and tear, based on defense through trenches, in which new weapons were used (toxic gases, machine guns) and in which millions of men died. Battles like Verdun or the Somme are good examples.
Meanwhile, at sea Great Britain subjected Germany to a maritime blockade that prevented the exit of the German fleet towards the Atlantic. In response, Germany opted for submarine warfare, sinking hundreds of Allied military and merchant ships and hindering the development of trade between the French and English and the United States.
3. The End of the War
At the end of 1917, this situation of balance between the two sides collapsed due to the confluence of two facts:
- Signing of the Peace of Brest-Litovsk between Russia and Germany. In October 1917, the Russian Revolution had triumphed and the Bolsheviks, led by Lenin, had come to power. They had come to power promising peace and an end to war. Russia will lose huge territories like Poland, the Baltic countries and Finland. Germany, on the contrary, managed to eliminate one of the two fronts.
- Joining the United States into war in support of Great Britain and France. The United States had strong commercial ties with those countries, which were endangered by the effects of the submarine warfare that the Germans carried out in the Atlantic.