Why did World War 1 even happen?

1the spark

June twenty-eighth, 1914, Sarajevo: Gavrilo Princip shoots Archduke Franz Ferdinand, heir to Austria-Hungary's throne. Within about five weeks, Europe's great powers were at war.

2the tinder

But one murder alone does not cause a world war. The shots were the spark; Europe was dry tinder: alliances, arms races, rival empires and nationalism.

3linked quarrels

Alliances linked the quarrels. Germany backed Austria-Hungary against Serbia, Russia stood behind Serbia, and France was Russia's ally. A Balkan quarrel now touched five capitals.

4five weeks

A fast fuse: blank cheque July 6, ultimatum July 23, war on Serbia July 28, Russia mobilising July 30, Britain at war August 4.

5war plans

Once Russia mobilised, Germany's plan sent most of its army west, through neutral Belgium. Britain had guaranteed Belgium in 1839, and declared war on August 4.

6choices

Nobody was forced: Italy, Germany's ally, stayed neutral, and Britain had no binding alliance with France. Each government chose, and historians still argue whose choices weighed most.

7the whole idea

So: tinder of alliances, arms races, rival empires and nationalism, one spark in Sarajevo, and governments choosing escalation. That, not one murder alone, made 1914.