The First World War has been described as the "primordial catastrophe of the twentieth century." Arguably, Italian Fascism, German National Socialism and Soviet Leninism and Stalinism would not have emerged without the cultural and political shock of World War I. The question why this catastrophe happened therefore preoccupies historians to this day. The focus of this volume is not on the consequences, but rather on the connection between the Great War and the long 19th century, the short- and long-term causes of World War I. This approach results in the questioning of many received ideas about the war's causes, especially the notion of "inevitability."