This chapter presents a historical overview of evolving patterns of warfare in preindustrial, industrial, and postindustrial societies. It examines the concept of the military revolution of the early modern era and the subsequent long-term changes in the patterns of the military conflicts such as the industrialization of war. The character of warfare changed dramatically from the medieval era to the French Revolution. Advancements in technology, adaptations in finances, the structure of the state, and more contributed to a period that scholars have debated as a military revolution. The Spanish forged a new centralized monarchy and a class of Christian warriors, hidalgos, through their struggle to expel the Moors from the peninsula. The English, for instance, opened a new avenue of funding while at the same time consolidating public debt by making government bonds available through a secondary market. New financial methods and governmental institutions facilitated the growth of the state.