Dietrich Heinrich von Bülow (1757–1807) served for sixteen years in the Prussian army, but for the remainder of his life lived a varied existence as a theatrical manager, preacher, writer, businessman, debtor and finally prisoner. It was not until after his death that this work, written in 1799 and reissued here in its 1806 English translation, began to find favour. He advocates the use of mathematical principles in devising swift and decisive tactics, and was one of the first theoreticians to regard tactics and strategy as separate concerns. At a time when Germany and Italy were yet to be unified, he writes that expansion to 'optimum' size would result in a Europe of only twelve states. The book's theories were criticised by Napoleon and Clausewitz, but had a considerable influence on the Prussian and Austrian armies of the late nineteenth century, and it is regarded as one of the founding texts of modern geopolitics.