World War I, also known as the First World War, the Great War, or the War to End All Wars, was a global war originating in Europe that lasted from 28 July 1914 to 11 November 1918. More than 70 million military personnel, including 60 million Europeans, were mobilised in one of the largest wars in history. It was one of the deadliest conflicts in history and precipitated major political change. The trigger for the war was the assassination of Archduke Franz Ferdinand of Austria, heir to the throne of Austria Hungary, by Yugoslav nationalist Gavrilo Princip in Sarajevo on 28 June 1914. This set off a diplomatic crisis when Austria Hungary delivered an ultimatum to the Kingdom of Serbia. Within weeks the major powers were at war and the conflict soon spread around the world. By the end of the war in November 1918, the German Empire, Russian Empire, Austro-Hungarian Empire and the Ottoman Empire ceased to exist. National borders were redrawn, with nine independent nations restored or created and Germany's colonies were parcelled out among the victors. During the Paris Peace Conference of 1919, the Big Four powers - Britain, France, the United States and Italy - imposed their terms in a series of treaties. The League of Nations was formed with the aim of preventing any repetition of such a conflict. This effort failed and economic depression, renewed nationalism, weakened successor states and feelings of humiliation eventually contributed to the start of World War II.