Warfare is the most dangerous threat faced by modern humanity. It is also one of the key influences that has shaped the politics, economics, and society of the modern period. But what do we mean by modern war? What causes modern wars to begin? Why do people fight in them, why do they end, andwhat have they achieved? In this accessible and compelling Very Short Introduction, Richard English explores the assumptions we make about modern warfare and considers them against the backdrop of their historical reality. Drawing on the wide literature available, including direct accounts of the experience of war, English provides an authoritative account of modern war: its origins, evolution, dynamics, and current trends.