This is a volume of comparative essays on the First World War that focuses on one central feature: the political and cultural "mobilization" of the populations of the main belligerent countries in Europe behind the war. It explores how and why they supported the war for so long (as soldiers and civilians), why that support weakened in the face of the devastation of trench warfare, and why states with a stronger degree of political support and national integration (such as Britain and France) were ultimately successful.