🌍 World War I (1914–1918): A Complete Summary
1. Background and Causes
World War I, also called the Great War, began on 28 July 1914 and lasted until 11 November 1918. It was primarily fought between two alliances:
- Allied Powers: Britain, France, Russia, Italy (later), USA (joined 1917)
- Central Powers: Germany, Austria-Hungary, Ottoman Empire, Bulgaria
Main Causes (M.A.I.N.)
| Cause |
Explanation |
| M – Militarism | Arms race among European powers. Germany and Britain competed in naval buildup. |
| A – Alliances | Formation of Triple Alliance (1882) and Triple Entente (1907) created bloc politics. |
| I – Imperialism | Competition for colonies in Africa and Asia increased hostility. |
| N – Nationalism | Ethnic groups sought self-determination (e.g., Serbs in Balkans). |
Immediate Cause: Assassination of Archduke Franz Ferdinand on 28 June 1914 at Sarajevo by Gavrilo Princip, a Bosnian Serb nationalist of the “Black Hand” group. Austria blamed Serbia → Germany supported Austria (“blank cheque”) → Russia supported Serbia → chain reaction → Europe plunged into war.
2. Alliances and Powers
| Allied Powers |
Central Powers |
| Britain | Germany |
| France | Austria-Hungary |
| Russia | Ottoman Empire |
| Italy (joined 1915) | Bulgaria |
| Japan, USA (1917) | — |
3. Major Events and Turning Points
Assassination at Sarajevo (June 1914)
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Austria declares war on Serbia (July 28, 1914)
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Germany invades Belgium → Britain enters war
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Battle of Marne (1914) – Germany stopped near Paris
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Trench Warfare begins on Western Front
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Gallipoli Campaign (1915) – Allied failure
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Italy joins Allies (1915)
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Battle of Verdun & Somme (1916) – massive casualties
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Russia collapses (1917) → Bolshevik Revolution
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USA enters war (April 1917)
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German Spring Offensive fails (1918)
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Armistice signed (Nov 11, 1918)
4. Theatres of War
| Front |
Description |
| Western Front | France-Belgium border, marked by trench warfare. |
| Eastern Front | Germany & Austria vs Russia; vast movements, heavy Russian losses. |
| Balkan Front | Serbia invaded early; later Greece joined Allies. |
| Middle Eastern Front | Arabs, aided by British (T.E. Lawrence), revolted against Ottoman rule. |
| African & Asian Fronts | Colonial troops fought; Japan took German colonies in Pacific. |
5. Important Battles
| Battle | Year | Significance |
| Battle of Marne | 1914 | Stopped German advance on Paris. |
| Battle of Gallipoli | 1915 | Allied failure; boosted Turkish nationalism. |
| Battle of Verdun | 1916 | Longest battle; symbol of French resistance. |
| Battle of Somme | 1916 | Massive casualties; introduced tanks. |
| Battle of Jutland | 1916 | Naval clash; Britain retained dominance. |
| Second Battle of Marne | 1918 | Turning point; led to German retreat. |
6. Role of Key Countries
- Germany: Aggressive militarism, U-boat warfare, introduced chemical weapons.
- Britain & France: Defended Western Front, faced huge casualties.
- Russia: Withdrew after 1917 Revolution; signed Treaty of Brest-Litovsk.
- USA: Entry in 1917 tipped balance in favor of Allies.
- Ottoman Empire: Defeated; collapse led to modern Turkey.
7. Technology and Warfare
| Weapon/Technology | Impact |
| Machine Guns | Caused mass deaths in trench warfare. |
| Tanks | First used in Battle of Somme. |
| Airplanes | Used for reconnaissance and bombing. |
| Poison Gas | Introduced by Germans; psychological terror. |
| Submarines (U-boats) | German naval strategy; attacked Allied supply ships. |
8. End of the War
Germany’s failure in the 1918 Spring Offensive and the arrival of US troops led to German collapse. Internal revolts and the abdication of Kaiser Wilhelm II followed. Armistice signed on 11 November 1918 ended fighting. The Treaty of Versailles (1919) formally ended the war.
9. Treaty of Versailles (1919)
| Clause | Terms |
| Territorial | Alsace-Lorraine returned to France; German colonies seized. |
| Military | Army limited to 100,000; no submarines or air force. |
| Economic | Reparations of 6.6 billion pounds imposed on Germany. |
| Political | League of Nations formed; Germany held responsible (Article 231). |
Post-War Treaties (1919 – 1920)
| Treaty |
With Whom |
Main Terms |
| Versailles | Germany (1919) | War guilt clause; reparations; loss of Alsace-Lorraine; disarmament. |
| St. Germain | Austria | Empire dissolved; territory to Czechoslovakia & Yugoslavia. |
| Trianon | Hungary | Reduced territory; loss to Romania & Yugoslavia. |
| Neuilly | Bulgaria | Minor territorial losses; reparations. |
| Sèvres / Lausanne | Ottoman Empire | Partition of Turkey; Lausanne (1923) revised boundaries. |
10. Consequences of the War
| Aspect |
Consequences |
| Political |
Fall of monarchies in Germany, Austria-Hungary, Russia, and Ottoman Empire. New states like Poland, Czechoslovakia, Yugoslavia, Finland emerged. League of Nations formed to maintain peace. |
| Economic |
Europe became bankrupt; industries destroyed; massive inflation and unemployment. The USA emerged as a global economic superpower. |
| Social |
Over 9 million soldiers killed, 20 million wounded. Rise of the “Lost Generation” and major social changes with women entering workforce. |
| Ideological |
Seeds of Fascism and Nazism sown due to humiliation of Germany. Bolshevik Revolution inspired communist movements worldwide. |
11. Summary Flow (Mindmap)
CAUSES → ALLIANCES → WAR BEGINS → MAJOR BATTLES
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TRIPLE ALLIANCE vs TRIPLE ENTENTE
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TRENCH WARFARE + TECHNOLOGICAL CHANGE
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USA ENTRY → GERMAN COLLAPSE
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TREATY OF VERSAILLES
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ECONOMIC RUIN → RISE OF FASCISM
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WORLD WAR II
12. Legacy
World War I reshaped global politics — empires disintegrated, new ideologies emerged, and power shifted to the USA. Ironically, the “war to end all wars” paved the way for World War II two decades later.
