How World War I Began: Causes and Events Explained
The First World War officially began in the summer of 1914, triggered by the assassination of Archduke Franz Ferdinand of Austria-Hungary on June 28 in Sarajevo. That single act is often presented as the moment Europe tipped into war, yet the assassination was only the spark. Beneath it lay decades of political tension, military planning, nationalism, imperial rivalry, and fragile diplomacy.
More than 17 million people would ultimately lose their lives, and tens of millions more were wounded or permanently scarred. Entire empires collapsed, borders were redrawn, and political systems were overturned. The conflict reshaped global power structures and left consequences that continue to influence international relations today.