This chapter offers an overview of six differently oriented interdisciplinary perspectives on theorising war. These are: legal, criminological, sociological, feminist, and cultural. The “metaphor of war” became a key part of debates around crime and responses to crime during the 1970s. Sociological approaches to war are cited as underdeveloped aspects of the discipline. J. Klein offers one way in which understandings of war could be further informed by a consideration of the state’s enlistment of public support for engaging in warfare. War is an expression of violence in the extreme that becomes both the opportunity and the vehicle for a wide range of other violence(s) not usually put in the same frame as war itself. The chapter concludes by considering the questions raised by each of these perspectives for the contemporary position of criminology in relation to the study of war.