The First World War began in 1914 and lasted to the final Armistice in 1918. The Allied Powers, led by the British Empire, France, Russia until March 1918, Japan and the United States after 1917, defeated the Central Powers, led by the German Empire, Austro-Hungarian Empire and the Ottoman Empire. The war caused the disintegration of four empires—the Austro-Hungarian, German, Ottoman, and Russian ones—as well as radical change in the European and West Asian maps. The Allied powers before 1917 are referred to as the Triple Entente, and the Central Powers are referred to as the Triple Alliance.
When did the first World War begin? 
1914