Europe's imperial powers had been engaged in economic and military rivalries for decades, but these became increasingly virulent during the first part of the 20th century. Great Britain's dominance of the seas came under aggressive challenge from Germany. Brooding over a defeat at the hands of Prussia in 1871, France aligned itself with Great Britain, its traditional enemy, against Germany. Britain, France, and Russia formed an alliance that pressured Germany on both its east and west borders. Germany, in tum, aligned with the ancient kingdom of Austria-Hungary and with the Turkish-ruled Ottoman Empire to its south. The world's great nations were in position for a fight, a single incident away from catastrophe.
On June 28, 1914, the heir to the Austro-Hungarian throne, Archduke Franz Ferdinand, was murdered - along with his wife - while touring the city of Sarajevo in the Austro-Hungarian province of Bosnia-Herzegovina. The assassin, Gavrilo Princip, acted on behalf of Serbian nationalists who sought to expel the Austrians from the Balkans and to create a larger Serbian state.
The assassination did not immediately lead to hostilities, but because Serbia was aligned with Russia, larger alliances were called into play and tensions were immediately heightened. When Serbia refused to investigate links between the assassins and members of the Serbian government, Austria-Hungary declared war on the Serbs in late July. Russia began to mobilize its enormous army to defend its ally, Serbia; Germany felt threatened and declared war on Russia soon after and then, on August 3, it went to war with France as well. The German army crossed into neutral Belgium on its way to France, prompting Britain to enter the war on France's side.
On one side were the Central Powers, made up of Germany, Austria-Hungary and, before long, the Ottoman Turks. Opposing them were the Allies: Britain, France, and Russia, along with Belgium and Serbia. The German attack on France through Belgium met with initial success, but the French regrouped at the Battle of the Marne and prevented a successful march on Paris. Tens of thousands lost their lives in a series of battles near the Belgian town of Ypres as both sides sought to command the continental coastline along the English Channel. The battles ended without a clear result but with massive casualties, establishing a terrible pattern for the war's western front.
With German forces engaged in France and Belgium to the west, Russia launched an offensive against Germany's eastern flank. Although the Russians oumumbered them, the Germans, under the command of Paul von Hindenburg and Erich Ludendorff, were able to outmaneuver and decisively defeat the Russians at the Battle of Tannenberg in early September 1914. A quarter million Russians were killed or wounded, while the Germans lost just over 10,000. Russia's defeat and losses foiled the Allies' plans for a holding action in the west to be accompanied by a massive Russian onslaught in the east. The Russian commander, Alexander Samsonov, committed suicide when he learned of his army's losses.
Most of the war took place in Europe, but battles also took place in Africa and Asia as the contending forces attempted to strip their rivals of colonial possessions. Intense fighting in German East Africa (present-day Tanzania) broke out when the Allies sought to expel German power there, and in Syria, Palestine, and present-day Iraq between the British and the Turks.
• The Western Front
The combatants on the western front dug miles of trenches to provide shelter from artillery shells. The trench came to symbolize the war on the western front, where progress was measured in yards and neither side seemed able to take the offensive without suffering devastating casualties. The weapons of war had changed more quickly than tactics. Now, a generation of generals and other senior officers failed to understand the power of well-placed machine guns. Troops in the trenches of the western front were periodically ordered "over the top" to charge enemy emplacements, and they died by the tens of thousands.
The British changed their strategy at the suggestion of Winston Churchill, who was First Lord of the Admiralty, Britain's supreme naval commander. However, their effort to get at Germany through an invasion of Turkey led to further disaster at Gallipoli, followed by ignominious retreat in late 1915. In another effort to break the deadlock, Britain and Germany engaged each other on the seas in the Battle of Jutland in the spring of 1916. The battle took place in the North Sea as the Germans attempted to break a British naval blockade of German ports. Twice during the battle, German warships outmaneuvered the vaunted Royal Navy, firing devastating broadsides. The British took heavy casualties but remained an active presence on the North Sea. Germany then decided to conduct its naval war from below the sea, using the newly perfected submarines to attack warships and merchant vessels alike.
Meanwhile, the fighting on land became more intense. In February 1916, the Germans attacked the French city of Verdun near the Meuse River in hopes of smashing the French defenders and demoralizing the civilian population. The French, despite being outnumbered, rallied under the leadership of General Philippe Petain and stopped the Germans cold. Meanwhile, the British launched an offensive of their own. The Battle of the Somme began when British soldiers came out of the trenches on the morning of July I to face heavily defended German positions along the River Somme. By the time night fell, nearly 20,000 were killed and 40,000 wounded in a single day of combat. The battles of Verdun and the Somme raged for months, resulting in 620,000 British casualties, 375,000 French, and more than 750,000 German. Very little ground changed hands, despite this unprecedented loss of life.
• The Eastern Front
The war was more fluid but no less bloody in the East. Russia took the offensive with new ally Romania, but the Germans thwarted the measure. The Russian czar, Nicholas II, was in personal command of his country's forces on the eastern front, leaving his wife, Queen Alexandra, to deal with an increasingly dissatisfied national legislature and a war-weary population. A rebellion against czarist rule broke out in St. Petersburg in March 1917, and the czar abdicated the throne on March 15. A new provisional government under Alexander Kerensky took power but continued the czar's war policy. Kerensky was overthrown in November when the Bolsheviks seized power under Vladmir Lenin and Leon Trotsky. The Bolshevik regime declared a truce and began peace negotiations with Germany, signing the Treaty of BrestLirovsk and ending the war on the eastern front.
With Germany able to focus exclusively on the western front, the already brutal combat escalated to unimaginable levels in the spring of 1917, which saw hundreds of thousands more casualties at Ypres and Passchendaele in the Flanders region of Belgium.
• America Enters the War
Good news for the Allies arrived in April 1917, when the United States, which had been neutral, declared war on the Central Powers after German submarines attacked American commercial ships in the Atlantic Ocean. President Woodrow Wilson proclaimed that this was "a war to make the world safe for democracy." By June 1917, the first American troops landed in France and saw action at Chateau-Thierry, helping to halt a German offensive. In March 1918, the Germans attacked the British near the French town of Amiens, but their offensive sputtered to a halt. They then turned their attention to the French capital Paris. The French rallied, however, at the second Battle of the Marne in the summer of 1918, shutting down the German offensive.
With the reinforcement of American troops, the Allies launched a major offensive in September 1918. American troops saw intense combat in multiple battles in the Argonne Forest, ultimately forcing Germany into retreat. German soldiers and civilians had become increasingly demoralized seeing the American involvement as a devastating development. Political and social unrest broke out at home due in large part to food shortages caused by a British naval blockade. The discouraged German government asked for peace terms with the Allies, and an armistice brought the war to an end on November 11, 1918.
In 1919, the victors presided over a peace conference in Paris. President Woodrow Wilson took center stage as a self-appointed honest broker, pushing hard for self-determination of all peoples. His "Fourteen Points" presented a plan for a League of Nations that would prevent future wars and included no punitive damages against the losing combatants. The European leaders, having suffered such enormous casualties, had different ideas. The French president Georges Clemenceau sniffed, "Mr. Wilson bores me with his 14 Points; why God Almighty has only 10!" Although they embraced Wilson's ideas publicly, behind closed doors, the British Prime Minister David Lloyd George and Georges Clemenceau drew up their own plans that essentially called for Germany to be treated as a conquered nation that was responsible for the war. The Treaty of Versailles forced Germany to pay reparations, return the regions of Alsace and Lorraine to France, and demilitarize the Rhineland, Germany's industrial heartland.
The humiliation of Germany was so complete that many Germans concluded their government had betrayed them. A young corporal named Adolf Hitler fanned the flames of discontent, declaring in 1922, "It cannot be that two million Germans have fallen in vain ... No, we do not pardon, we demand- vengeance!"
(‘The New York Times ‘Smarter by Sunday – 52 Weekends of Essential Knowledge for the Curious Mind’)