World War I, also known as the Great War, began in 1914 and lasted until 1918. Its roots trace back to a complex web of political, military, and economic tensions in Europe. The assassination of Archduke Franz Ferdinand of Austria-Hungary on June 28, 1914, in Sarajevo, was the immediate catalyst, but the war had deeper causes. The major contributing factors included nationalism, imperialism, militarism, and the entangled alliances between the major powers of Europe.
By the early 20th century, Europe was divided into two major alliance blocs. The Triple Alliance consisted of Germany, Austria-Hungary, and Italy, while the Triple Entente included France, Russia, and Britain. These alliances were originally formed for defensive purposes, but they increased tensions and the risk of a broader conflict. When one country was drawn into conflict, others followed due to treaty obligations.
On June 28, 1914, Archduke Franz Ferdinand, the heir to the Austro-Hungarian throne, and his wife, Sophie, were assassinated in Sarajevo by Gavrilo Princip, a Bosnian Serb nationalist affiliated with the Black Hand secret society. Austria-Hungary saw this as an opportunity to punish Serbia and issued an ultimatum. Serbia's partial rejection of the demands led Austria-Hungary to declare war on July 28, 1914.
After Austria-Hungary declared war on Serbia, a chain reaction occurred. Russia mobilized in defense of Serbia. Germany declared war on Russia and then on France. When Germany invaded Belgium to reach France, Britain declared war on Germany. Soon, the conflict expanded into a world war involving numerous nations across multiple continents.
The Western Front, stretching from the North Sea to the Swiss border, became synonymous with trench warfare. After the failure of Germany’s Schlieffen Plan to quickly defeat France, both sides dug in. Trench warfare led to a grueling stalemate with horrific conditions, including mud, disease, and constant shelling. Major battles like the Somme, Verdun, and Ypres saw massive casualties for minimal territorial gains.
In the East, Germany and Austria-Hungary faced Russia. Unlike the static Western Front, the Eastern Front was more fluid, with large-scale movements of armies. Russia initially made gains but was pushed back by German forces. The war strained Russia economically and socially, contributing to the 1917 Russian Revolution.
Naval warfare played a crucial role in World War I. Britain imposed a naval blockade on Germany, cutting off vital supplies. Germany responded with unrestricted submarine warfare, targeting Allied and neutral ships. The most infamous case was the sinking of the RMS Lusitania in 1915, which killed 1,198 people, including 128 Americans. This event contributed to shifting American public opinion against Germany.
World War I was a truly global conflict. Colonies in Africa and Asia were drawn in, as imperial powers mobilized their resources. Battles occurred in Africa, the Middle East, and even in the Pacific. Countries such as Japan entered the war on the side of the Allies, while others, like the Ottoman Empire, joined the Central Powers.
The United States initially remained neutral. However, repeated German submarine attacks on American ships and the discovery of the Zimmermann Telegram — a German proposal for a military alliance with Mexico — led the U.S. to declare war on Germany on April 6, 1917. The American entry provided the Allies with fresh troops, resources, and morale, which proved decisive.
In 1917, the Russian Revolution led to the abdication of Tsar Nicholas II. The Bolsheviks, led by Vladimir Lenin, seized power and sought to end Russia’s involvement in the war. In March 1918, Russia signed the Treaty of Brest-Litovsk with Germany, ceding large territories in exchange for peace. This allowed Germany to focus more on the Western Front.
With the arrival of American forces, the Allies launched a series of offensives in 1918 known as the Hundred Days Offensive. These operations pushed German forces back and led to the collapse of the Central Powers. Facing military defeat and internal unrest, Germany requested an armistice.
The armistice was signed on November 11, 1918, at 11 a.m. — the eleventh hour of the eleventh day of the eleventh month. The war ended with Germany’s defeat and the collapse of the Austro-Hungarian, Ottoman, and Russian empires. The final death toll was staggering: over 16 million people died, including soldiers and civilians.
The Treaty of Versailles was signed on June 28, 1919, exactly five years after Franz Ferdinand’s assassination. It imposed harsh penalties on Germany, including territorial losses, military restrictions, and massive reparations. The treaty also established the League of Nations, an international organization aimed at preventing future conflicts. However, the treaty’s punitive terms sowed the seeds for World War II.
World War I saw the introduction of new and deadly technologies: machine guns, tanks, poison gas, aircraft, and submarines. These innovations changed the nature of warfare. Airplanes were first used for reconnaissance and later for bombing and dogfights. The tank, introduced by Britain in 1916, was designed to break the trench deadlock.
The psychological trauma of World War I was immense. Soldiers suffered from "shell shock" — a term used at the time for what we now understand as PTSD. The horrors of trench warfare and the scale of death left a generation disillusioned. This sense of despair was captured in literature by writers like Wilfred Owen, Siegfried Sassoon, and Erich Maria Remarque.
With millions of men at the front, women stepped into roles traditionally held by men — in factories, offices, and even in auxiliary military units. Their contributions were vital to the war effort and led to greater social and political rights, including women's suffrage in several countries after the war.
World War I pushed medical science forward. Techniques for treating wounds, managing infections, and performing surgery improved. Blood transfusions became more common, and antiseptics were used more effectively. The war also highlighted the need for mental health care for soldiers.
Four major empires fell due to World War I: the German, Austro-Hungarian, Ottoman, and Russian empires. New nations emerged in their place, such as Czechoslovakia, Yugoslavia, and Poland. The geopolitical map of Europe and the Middle East was redrawn, often without regard for ethnic or cultural realities, leading to future conflicts.
World War I reshaped the modern world. It ended the age of empires, changed societies, and introduced new ideologies. It led to the rise of fascism, communism, and the eventual outbreak of World War II. The League of Nations failed to prevent further conflict, but the lessons of World War I influenced the formation of the United Nations after World War II.
Today, World War I is commemorated globally. November 11 is observed as Armistice Day, Veterans Day, or Remembrance Day in many countries. War memorials, cemeteries, and literature continue to honor the sacrifices of those who fought. The phrase “Lest we forget” serves as a reminder of the war's horrors and the importance of peace.
World War I was a cataclysmic event that changed the course of history. Its causes were complex, its battles devastating, and its consequences long-lasting. Understanding the complete history of the Great War is essential to grasp the dynamics of the 20th century and the lessons we must carry forward into the future.