Causes of World War I
Alliances, militarism, imperialism and nationalism pushed Europe toward war.
About this topic
World War I began in 1914 after a complex mix of long-term causes, often remembered by the letters MAIN: militarism, alliances, imperialism and nationalism. Militarism meant an arms race, especially Britain and Germany building battleships, and plans such as Germany's Schlieffen Plan for a quick war.
Alliances divided Europe into the Triple Alliance (Germany, Austria-Hungary, Italy) and the Triple Entente (France, Russia, Britain), so a local conflict could drag everyone in. Imperial rivalry for colonies caused crises in Morocco, while nationalism, especially Slavic nationalism in the Balkans, challenged Austria-Hungary and the weak Ottoman Empire.
The spark came on June 28, 1914, when Gavrilo Princip, a Bosnian Serb nationalist, assassinated Archduke Franz Ferdinand, heir to the Austro-Hungarian throne, in Sarajevo. Austria-Hungary, with Germany's blank cheque of support, issued an ultimatum to Serbia and declared war; Russia mobilized to defend Serbia, Germany declared war on Russia and France and invaded neutral Belgium, bringing in Britain. Within weeks the continent was at war. Like dominoes falling, alliances turned a regional crisis into a world war. Misconception: the assassination alone did not cause the war; it was the trigger for tensions already present. Historians still debate how much blame each nation bears.
Key ideas
- MAIN causes
- Assassination of Franz Ferdinand
- Alliance system
Quick check
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Frequently asked questions
What is Causes of World War I?
Alliances, militarism, imperialism and nationalism pushed Europe toward war.
What will I learn in Causes of World War I?
MAIN causes. Assassination of Franz Ferdinand. Alliance system.
Is Causes of World War I part of World History?
Yes. It is one of 80 World History topics on LearnViz HighSchoolEdu, with 3 key ideas, a live animation and a quick check.
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