World War I, also known as the Great War, was a global conflict that lasted from 1914 to 1918, primarily involving the major powers of Europe. The war was characterized by a complex web of alliances, territorial disputes, and political rivalries. Two major alliances were the Central Powers, composed of Germany, Austria-Hungary, the Ottoman Empire, and Bulgaria, and the Allies, initially composed of France, Russia, and the United Kingdom, later joined by Italy, the United States, and other countries. The assassination of Archduke Franz Ferdinand of Austria by a Serbian nationalist in Sarajevo on June 28, 1914, set off a chain reaction that led to the mobilization of forces and declaration of war among the European powers. The Central Powers and the Allies engaged in a series of battles on multiple fronts, most notably the Western Front, characterized by trench warfare, and the Eastern Front, with vast, fluid movements of armies. ## New weapons of destruction World War I introduced new weaponry and tactics, including machine guns, extensive use of artillery, poison gas and other chemical weapons, tanks, submarines, and aerial combat. These innovations led to a prolonged and deadly conflict that resulted in significant casualties, with an estimated 8.5 million combatants and 6-13 million civilians losing their lives. The war also had profound political, social, and economic impacts. The Russian [[Bolshevik Revolution]] of 1917 led to the withdrawal of Russia from the war and the establishment of the Soviet Union and [[Communism]]. The war's nearing end would see the dissolution of several empires, including Austria-Hungary, the German Empire, the Ottoman Empire, and the Russian Empire, and the redrawing of national borders. ## End of World War I The fighting came to an end on November 11, 1918, with the signing of the armistice agreement between Germany and the Allied Powers. This marked the cessation of fighting on the Western Front, which took effect at the 11th hour of the 11th day of the 11th month of 1918. The [[Treaty of Versailles]], signed on June 28, 1919, marked the official end of the war between Germany and the Allied Powers. The treaty imposed harsh penalties on Germany, including substantial monetary reparations, territorial losses, and limitations on military capabilities. These punitive measures contributed to feelings of resentment and humiliation among the German population, which later became a factor in the rise of [[Adolf Hitler]] and the [[Nazis]], ultimately leading to the [[World War II Timeline]].