Gunpowder, and the chemical explosives which followed it, released a form of energy that has helped shape the modern world. From its early origins in c.mid-ninth century China this explosive knowledge spread across Asia and the Arab lands to the West, making possible the formation of states and the creation of empires. But the growing domination of the world by western Europe was not based upon superior firepower alone, but upon a nexus of factors that combined to encourage trade, exploration, settlement, mining and civil engineering. The search for saltpetre, for example, an essential ingredient of gunpowder, became a powerful engine of sea-going European trade from the early seventeenth century. Smaller states like Venice were unable to form these distant connections, and so to sustain a gunpowder army. Stronger states like France and Britain were able to do so, and became even more powerful as the demand for improved explosives fostered national strengths - leading to a development of the sciences, especially chemistry, in the former case, and of manufacturing techniques in the latter.But despite its significant role in global enterprises, the technology of gunpowder making has until recently been neglected by historians, viewed especially by military historians as a 'given factor'. The publication of the earlier volume entitled Gunpowder: The History of an International Technology (1996), arranged by the present editor and with many of the same contributors, marked a significant step in the recognition of the importance of this subject. The new volume builds upon this expertise by presenting the current and original research of this body of scholars, who meet regularly under the auspices of the International Committee for the History of Technology.