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. Social historians might study the everyday experiences of rank-and-file soldiers, or consider how life changed for the families whom soldiers left behind. Alternately, they might examine antiwar and resistance movements, or the ways in which ordinary people coped with the horrors of extreme violence. Cultural historians might consider war as a subject of epic poetry, triumphant sculpture, or martial music. They might also look at popular cultures of war, or at how new forms of communication (books, posters, films) have often permitted new varieties of propaganda. Historians of technology examine not only shifts in weaponry, from the spear to the drone, but also other transformations in material culture (canned food) and communication methods (the telegraph, social media). Yale historians study and teach about the causes, nature, and consequences of warfare in all corners of the world, from antiquity to the present.