World War I Origins

The Franco-German war between the French Empire and the Confederation of North Germany led to the formation of the German Empire in 1871.
Alsace and Moselle were annexed to the German Empire, leading to frustration from the French side.

Germany advanced its industry and economy, and formed alliances with the Austro-Hungarian Empire and Italy.
Germany began colonizing African territories, leading to the formation of the Triple Alliance.
The British Empire feared the rise of the German army and navy, and formed alliances with France and Russia, creating the Triple Entente.

A young Serbian nationalist from Bosnia murdered the heir to the throne of Austria and his wife in Sarajevo on June 29, 1914.
Austria-Hungary accused Serbia of organizing the attack and declared war, leading to a spread of conflict between the Triple Entente and the Triple Alliance.

Germany invaded Luxembourg and Belgium, violating their neutrality, and the French, British, and Belgian armies were forced to retreat.
The German army turned away from Paris to surround the French army, but were attacked on the flanks and forced to retreat.

The war frontlines stabilized, with 700 km of trenches stretching from the North Sea to Switzerland.
Germany sent troops to the east to fight against a Russian offensive, and the Ottoman Empire decided to support Germany.
New fronts opened in the Caucasus, Sinai, and Kuwait, with Britain supporting an Arab rebellion against the Ottoman Empire.

Italy declared war on Austria-Hungary, and Japan went to war against Germany, seizing its colonies in the Pacific and China.
French, British, and Belgian forces stormed German colonies in Africa.
Many people from colonized territories were enlisted in European armies, with France mobilizing nearly 800,000 people and the British Empire enlisting 2.7 million men.

Germany became the first to organize aerial bombardments, and the air force was used for tracking and reconnaissance, with the first aerial battles.
Germany launched submarine wars in British territorial waters, sinking ships.
Both sides used toxic gases, causing many casualties.

The United States of America entered the war alongside the Allies after suffering from the commercial blockade in the Atlantic.
Russia suffered over 1.7 million military casualties, and a revolution led to the signing of a ceasefire with the Central Empires.
Germany concentrated its troops on the west and succeeded in a breakthrough, but the French army counterattacked and disintegrated German defenses.
The German army retreated, and the Allies led on all fronts, leading to the signing of the Armistice on November 11, 1918.

The Treaty of Versailles was signed on June 28, 1919, with Germany and its allies held solely responsible for war damages.
Germany was forced to accept all demands of the victors, pay heavy compensation, and cede roughly 15 percent of its territory to France, Belgium, Denmark, and Poland.
The humiliation imposed upon Germany left it with a desire for revenge.

Franco-German war led to the formation of the German Empire in 1871, causing France to lose Alsace and Moselle.
The annexation of Alsace and Moselle led to frustration from the French side.

Germany advanced its industry and economy, forming alliances with the Austro-Hungarian Empire and Italy.
Germany's colonization of African territories led to the formation of the Triple Alliance.
Britain feared Germany's rising army and navy, forming alliances with France and Russia, creating the Triple Entente.

On June 29, 1914, a young Serbian nationalist from Bosnia killed the heir to the throne of Austria and his wife in Sarajevo.
Austria-Hungary accused Serbia of organizing the attack and declared war.

Germany invaded Luxembourg and Belgium, violating their neutrality, leading to a retreat of French, British, and Belgian armies.
Germany's army turned away from Paris to surround the French army, but was attacked on the flanks and forced to retreat.

The war frontlines stabilized, with 700 km of trenches stretching from the North Sea to Switzerland.
Germany sent troops to the east to fight against a Russian offensive, and the Ottoman Empire supported Germany.
New fronts opened in the Caucasus, Sinai, and Kuwait, with Britain supporting an Arab rebellion against the Ottoman Empire.

Italy declared war on Austria-Hungary, and Japan went to war against Germany, seizing its colonies in the Pacific and China.
French, British, and Belgian forces stormed German colonies in Africa.
Over 800,000 people from colonized territories were enlisted in European armies, including nearly 800,000 in France and 2.7 million in the British Empire.

Germany organized the first aerial bombardments, and air forces were used for tracking and reconnaissance.
Germany launched submarine wars in British territorial waters, sinking ships.
Both sides used toxic gases, causing many casualties.

The United States entered the war alongside the Allies after suffering from the commercial blockade in the Atlantic.
Russia suffered over 1.7 million military casualties, leading to a revolution and a ceasefire with the Central Empires.
Germany concentrated its troops on the west and succeeded in a breakthrough, but the French army counterattacked and disintegrated German defenses.
The German army retreated, and the Allies led on all fronts, leading to the signing of the Armistice on November 11, 1918.

The Treaty of Versailles was signed on June 28, 1919, holding Germany and its allies solely responsible for war damages.
Germany was forced to accept all demands of the victors, pay heavy compensation, and cede roughly 15 percent of its territory to France, Belgium, Denmark, and Poland.
The Treaty of Versailles left Germany with a desire for revenge.