It is perhaps the most significant technological change in the history of warfare. The Middle Ages would see a new type of weapon emerge - the gun. This special issue looks at the invention of firearms, beginning in China, its spread throughout Eurasia and its influence on battles, armies and fortifications. Featuring articles by Tonio Andrade, Ruth Brown, Kelly DeVries, Kay Smith and more. One key aspect of this book is to show how experimental the use of guns and gunpowder is. In medieval China, Europe and Asia, there is a lot of new things happening in how warfare is being conducted. For example, how are cannons being used on the battlefield, and when are they successful (or unsuccessful) in changing the outcomes of battles? How do fortifications change, and how much of that is because of the threat posed by artillery? I want to give a sense to the reader that this is really a dynamic period, with new technology leading us to different and unexpected places, much like the computer revolution we are now in is changing our own society in unforeseen ways.