At its heart a history of the sixteenth century, this account of imperial competition for minerals focuses on the superpower of the day, Spain under Charles V and Philip II. It underlines the importance of new sources of money, above all silver, in understanding the rises and falls of ambitious rulers and their dependence on lenders in Bavaria, Genoa, Antwerp, and, ultimately, Amsterdam to sustain their expensive enterprises. The biggest bonanza was the discovery of silver in Potosí (located in today's Bolivia), whose large output was augmented by major improvements in extraction technology. The silver traveled eastward to Europe (mainly to repay lenders and to pay troops, but also to build and replace the Spanish Armada) and westward to finance growing trade with China, whose demand for silver seemed unlimited. This period was similar to the present in two respects: it was marked by globalization (the spread of diseases and cultivable plants, including cacao, changed the world forever) and fiscal profligacy.