The historical study of war begins with military history: battles and wars, generals and troops, tactics and strategy. Historians recognize that wars have been waged for many reasons, however, including dynastic ambition, religious sectarianism, and political ideology. To understand how war works, a broad range of methods must be brought into play. By looking at political history, we can see how domestic conflicts and constitutional debates have shaped the ways in which wars were fought, and explore the consequences—territorial, political, institutional—of victory and defeat.