The First World War

In June 1914 a Serbian nationalist, Gavrilo Princip, shot Archduke Franz Ferdinand — heir to the Austro-Hungarian throne — on a street in Sarajevo. Austria-Hungary blamed Serbia and declared war; Russia mobilized to defend Serbia; Germany backed Austria-Hungary and, to beat Russia's slow mobilization, invaded France first by marching through neutral Belgium — which brought Britain in. Within six weeks a regional quarrel had become a continental war: the Central Powers (Germany, Austria-Hungary, the Ottomans, Bulgaria) against the Allies (France, Britain, Russia, later Italy, and the United States in 1917). Each side expected to win by Christmas. Instead, machine guns, artillery, and barbed wire made attacking suicidal, and the armies dug 400 miles of trenches from the Channel to Switzerland and stayed there for four years, killing roughly seventeen million people over a few miles of mud. Four empires — German, Austro-Hungarian, Ottoman, and Russian — did not survive it, and the confident European order that had ruled much of the planet destroyed its own authority.