What Caused World War 1?
The Great War erupted in 1914 after decades of building tensions. One assassination lit the fuse.
Long-Term Causes
Alliance System
Europe divided into two armed camps: - Triple Alliance: Germany, Austria-Hungary, Italy - Triple Entente: France, Russia, BritainAn attack on one meant war with all.
Imperial Rivalries
European powers competed for colonies, markets, and prestige. Germany, arriving late to imperialism, demanded its "place in the sun."Nationalism
Ethnic groups sought independence or unification. In the Balkans especially, nationalist tensions simmered.Militarism
Arms races (especially Germany vs. Britain in naval power) created massive standing armies and war plans ready to execute.The Spark
June 28, 1914: Archduke Franz Ferdinand, heir to Austria-Hungary, was assassinated in Sarajevo by Gavrilo Princip, a Bosnian Serb nationalist.
Austria-Hungary blamed Serbia. Russia backed Serbia. Germany backed Austria-Hungary. France backed Russia. Alliances activated like dominoes.
The July Crisis
- July 28: Austria-Hungary declared war on Serbia
- July 30: Russia mobilized
- August 1: Germany declared war on Russia
- August 3: Germany declared war on France, invaded Belgium
- August 4: Britain declared war on Germany
Within six weeks, most of Europe was at war.
The Human Cost
- 9 million soldiers dead
- 21 million wounded
- Empires collapsed (German, Austro-Hungarian, Ottoman, Russian)
- The seeds of WW2 were planted
Related Reading
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