Few social scientists expected another major inter-state war in Europe. The dominant positions either confine warfare to the dustbin of European history or downplay its significance in late modernity. Sociologists of war have been less surprised by recent developments, however. In a wider socio-historical context warfare remains a crucial catalyst of social change. No other social phenomenon has continuously influenced the social world to such an extent and this has been particularly the case in European history. In this article, I critically review recent developments in the sociology of war. I also look at the ways in which existing analytical tools can be deployed to explain the return of inter-state warfare in Europe. I argue that the integration of longue durée comparative historical sociology with micro-sociological scholarship on everyday behaviour in war is the best way forward to understanding the long-term dynamics of war and society.