Although he produced over one hundred maps which were copied and reprinted hundreds of times over the course of more than a century, Giacomo Gastaldi (ca. 1500-1566) remains an understudied and somewhat enigmatic figure in the history of cartography. Giacomo Gastaldi Maps the World is the first monograph in any language devoted to the most important Italian cartographer of the sixteenth century, a man whose maps provided the first detailed and authoritative coverage of the entire earth. Besides relating all known biographical data on the cartographer, Douglas Sims's pioneering study contains a wealth of information on sixteenth-century cartography in general, on the study and interpretation of maps, and technical aspects of their engraving and publishing. He delves deeply into sixteenth-century theories of the continents, the mythical Gulf of Anian (a prefiguration of the Bering Strait), the medieval Arabic geographer Abulfeda, and on Giovanni Baptista Ramusio, who compiled the most complete record of the great age of exploration. The study concludes with a detailed cartobibliography describing 136 maps which can be attributed to Gastaldi, and a bibliography of more than 700 sources.