Providing a new interpretation of the origins of the First World War, this textbook synthesises recent scholarship and introduces the major historiographical and political debates surrounding the outbreak of the war. William Mulligan argues that the war was a far from inevitable outcome of international politics in the early twentieth century and suggests instead that there were powerful forces operating in favour of the maintenance of peace. His fresh perspective on the pre-war international system takes account of new approaches to the study of international politics since the end of the Cold War and the acceleration of globalisation. Thematic chapters examine key issues, including the military, public opinion, economics, diplomacy and geopolitics, and analyse relations between the great powers, the role of smaller states, the disintegrating empires and the July crisis. This compelling account will significantly revise our understanding of diplomacy, political culture, and economic history from 1870 to 1914.