World War I, also known as WWI, the First World War, and the Great War, is a global conflict that lasted between July 28, 1914 and November 11, 1918. Its primary combatants were the Allied Powers against the Central Powers. Nine million soldiers and seven million civilians lost their lives because of the war, and it was the second-deadliest event in human history, surpassed only 19 years later by its successor World War II.
World War I began when the Black Hand, a secret society of Serbian terrorists/nationalists, attempted to assassinate Austro-Hungarian royalty Archduke Franz Ferdinand. While the six-man assassination team was at first a failure when they tried bombing Ferdinand's cart, Gavrilo Princip eventually did the job by simply walking up to Ferdinand's cart while it was parked on the street and gunning him and his wife down with an FN M1910. Austria-Hungary immediately declared war on Serbia in response, which was followed by the Russian Empire declaring war on Austria-Hungary not only to protect its ally Serbia but to loosen Austria-Hungary's influence over the Balkans with war. The French Third Republic soon followed Russia's example, and the German Empire entered the war on Austria-Hungary's side.