For millennia, wars have raged across the world, splintering nations, creating empires, and triggering widespread human suffering. But why are countries propelled into battle? What determines victory or defeat? And how have key wars altered the course of history? In Wars that Changed the World, these questions are answered through the stories of 25 major world conflicts. Opening with the Great Peloponnesian War almost 2500 years ago, and closing with the ongoing War on Terror, these momentous clashes encompass every historical era, and stretch to all corners of the globe. Military historian Charles Messenger examines the historical background and the diverse reasons for the conflict - whether ideological, religious, or a personal struggle for power - and sheds light on the legacy of the war and its impact on the wider world. Complementing these compelling narratives are timelines detailing the period, maps of the region illustrating sites of major battles and theatres of war, and iconic images encapsulating the drama of the battle and the personalities involved. These enlightening accounts not only provide concise histories of particular campaigns and confrontations, but also add up to a fascinating and accessible overview of world history. Included are profiles of Alexander's Conquests, The Spanish Conquest of Mexico, The Seven Years War, The American War of Independence, The Napoleonic Wars, The American Civil War, The First and Second World Wars, Vietnam, and many other conflicts that have had a decisive impact on the world.