The causes of World War I, which began in central Europe in late July 1914 and finished in 1918, included many factors, such as the conflicts and hostility of the four decades leading up to the war.Militarism, alliances, imperialism, and nationalism played major roles in the conflict as well. The immediate origins of the war, however, lay in the decisions taken by statesmen and generals during the Crisis of 1914, casus belli for which was the assassination of Archduke Franz Ferdinand (the Archduke of Austria Hungary) and his wife Sophie by Gavrilo Princip, an irredentist Serb. The crisis came after a long and difficult series of diplomatic clashes between the Great Powers (Italy, France, Germany, the British Empire, the Austria-Hungarian Empire and Russia) over European and colonial issues in the decade before 1914 that had left tensions high.