What event triggered the start of World War I?

The Assassination

On June 28, 1914, Archduke Franz Ferdinand, who was next in line to become emperor of Austria-Hungary, was visiting Sarajevo. A young Serbian man named Gavrilo Princip shot and killed Franz Ferdinand and his wife Sophie. Princip was part of a group that wanted Serbia to be independent and free from Austria-Hungary's control.

Austria-Hungary's Declaration of War

Austria-Hungary blamed Serbia for the assassination and declared war on July 28, 1914. The government believed that Serbian officials had helped plan the attack. This declaration of war was the official start of the conflict that would become World War I.

The Chain Reaction of Alliances

Once Austria-Hungary declared war on Serbia, other countries joined the fighting because of alliances they had made with each other. Russia supported Serbia, Germany supported Austria-Hungary, France supported Russia, and Germany invaded Belgium to attack France. Within weeks, most major European powers were at war with each other.

Why This Event Mattered So Much

The assassination itself did not directly cause the war, but it was the spark that ignited tensions that had been building for years. European countries had created complex alliances and were competing for power and resources. The death of Franz Ferdinand gave Austria-Hungary a reason to start a conflict that pulled all of Europe into war.