Causes of World War I

On the morning of June 28, 1914, a nineteen-year-old Bosnian Serb named Gavrilo Princip stood on a Sarajevo street corner, apparently defeated. He had already botched his part in an assassination plot earlier that day. The target's motorcade had taken a different route, the first attempt had failed, and Princip had drifted away from his assigned position. Then the driver of Archduke Franz Ferdinand's open-topped car made a wrong turn, stalled the engine while trying to reverse, and stopped almost directly in front of him. Princip stepped forward. He drew his pistol. Two shots. The Archduke and his wife Sophie were dead within the hour.

Five weeks later, most of Europe was at war.

The sheer speed of the escalation, from a political murder in a provincial Balkan city to a continental catastrophe involving millions of soldiers, only makes sense if you understand what had been building beneath the surface of European politics for decades. The assassination did not cause the war. It triggered a system that was already primed to fire.