This book explores the issues associated with thinking the body at war. Ultimately, it reframes the relationship between the body and war by suggesting a new way of thinking about what 'the body' is, and consequently how we can consider it in relation to war. Although 'the body' may appear to be an unproblematic concept, through the prism of war it starts to become more difficult to grasp. Rather than being a material object with a certain given significance and with a given set of capabilities, the body emerges as being thoroughly contaminated by politics and culture.While efforts to render the body amenable to scientific knowledge and certainty abound, the very variety of these efforts suggests that they are not neutral scientific tools (whatever this might mean) but active in the construction of bodies of certain types. In other words, the body does not exist independently of our efforts to understand and alter it. This underlines the necessity for thinking the body and war, for thinking war without the body depends on a prior exclusion of the body which creates the body as a certain kind of entity which is amenable to exclusion. Every time we describe, invoke or omit the body, we are actually engaged in an active politics of creation, involved in the determination and definition of the body.If the body is actually actively created wherever it seems to be passively invoked, then it becomes more difficult to determine once and for all what the body is. Scientific and technological determinants of the body begin to appear to be provisional constructions of the body, rather than eternal truths. This leads to the conclusion, reinforced by the work of Deleuze and Guattari, that the body has no final form or substance, but is defined in virtue of its constant capacity for change. This has important implications for thinking about the body and war, and the book suggests that these implications have an ethical significance which reinforces the importance of thinking from the point of view of the unknown body. Rather than being simply anchored in geo-political space and linear time, war begins to appear through its affects on the body, for example, through post-traumatic stress disorder, or 'shell-shock'. It becomes possible to see war in terms of the way in which it is enacted and performed by the body, and in this sense it becomes a more elusive term which is intrinsically corporeal not only in its effects (in terms of the bodies it mobilises and damages) but in terms of an ongoing negotiation with the resonances of war which may take place long after battle has ostensibly ceased, and which may permeate apparently non-militarised areas of society.This book chimes with a range of themes current in contemporary scholarship. For example, the question of how to diagnose trends in contemporary war and the War on Terror has provoked a number of responses from those such as Michael Dillon, Julian Reid and Luis Lobo-Guerrero who are concerned to interrogate how war intersects with political ontology and is productive of a certain mode of governance. While indebted to these readings for a number of insights, this book differs from them in regarding war not so much in terms of a martial science, but as a social and cultural phenomenon whose effects are immanent and intimate. This book's desire to posit the unknown body as an ineluctable ethical dimension in all thought relates to, but differs from, the works of Judith Butler and Maja Zehfuss which seek to reconsider what our ethical responsibilities and responses in relation to war might be. The book is original in bringing the work of Gilles Deleuze and Félix Guattari to bear on thinking about the body and war, and may therefore serve to introduce these thinkers to a new audience.