As wars and other conflicts increase on a worldwide scale, the alleged ‘new wars’ of the present day have taught that military victory does not necessarily result in a sustained state of peace. Rather, societies in conflict experience a ‘status mixtus’ - a transformative period that includes substantial changes in economy, politics, society and culture. Focusing on these decades of reconstruction in Europe and North America, this book examines the transformation of state systems, international relations, and normative principles in international comparison. By putting the postwar decade after 1945 into a long-term historical perspective, the chapters illuminate new patterns of transition between war and peace from the eighteenth to the twentieth century. Experts in the field show that states and societies are never restituted from a ‘zero hour’. They also demonstrate that foreign and domestic policy are intermixed before and after peace breaks out.