When the Great War erupted, the Ottoman Empire was already depleted from years of conflict in the Balkans and elsewhere. Why, then, were the Ottomans so quick to join the Central Powers in early November 1914? The immediate answers involve internal Ottoman politics and a struggle for dominance within the Young Turk ruling elite. This presentation examines the Ottoman decision within the broader context of European relations and the challenges caused by the rise of competing forms of nationalism within the Empire, issues which shape the history of the Middle East throughout the war and the century that followed.