This chapter investigates the weaponry available to both armies and navies of the Napoleonic wars and their improvement during the period. This was very much a period of improvement rather than an era seeing the introduction of radical new technologies in the fields of weaponry and tactics. However, by the greater use of industrial processes, it became possible to greatly increase the number of arms available and thus the size of the combatting forces it was possible to put into the field. The greatest improvements however were undoubtedly in the field of artillery, which were made more powerful with the improved quality of gunpowder, while the weight of artillery pieces was reduced significantly, allowing them to be far more manoeuvrable on the battlefield. This allowed them to begin the process of achieving the domination of the battlefield that was so obvious in the First World War.