This is the first volume of a projected three volume series charting the causes of war from 3000 BCE to the present day. Written by Alexander Gillespie, a leading international lawyer, and using as its principal materials the documentary history of international law (largely in the form of treaties and the negotiations which led up to them), these volumes explain what the treaties can tell us about the causes of war. In departing from the various theories put forward by historians, anthropologists, and psychologists - for instance, that warfare stems from disputes over private property, or that warfare is inherent in human behavior - Alexander Gillespie offers a different taxonomy of the causes of war, which, he explains can be grouped under the headings of politics, religion, migration, and empire-building. The Causes of War will be a fascinating study for international lawyers and legal historians with an interest in the laws of war and armed conflict.