World War I

World War I, also known as the First World War and the Great War, was a conflict occurring from 1914 to 1918. It was by far the largest war in history until the advent of World War II.

World War I radically changed the face of Europe. The German, Austro-Hungarian, Ottoman, and Russian Empires, along with their four dynasties, whose roots went back to the days of the Crusades, all fell during or after the war. The collapse of the existing world order precipitated deep political, social, and economic changes. Communist revolutions spread throughout Europe and led to the establishment of the first Communist state, the Soviet Union, in 1922. From the ravages of absolutist monarchies, several new states emerged or were recreated, including Czechoslovakia, Yugoslavia, ...