The origin of nautical cartography: certitudes, doubts, and perplexities

Abstract

ABSTRACT European geographical maps and nautical charts have distinct geneses and underwent separate evolutions. When scientific cartography was reborn in the beginning of the fifteenth century, following the translation and dissemination of Ptolemy’s Geography, the portolan chart had already been established as an effective navigational tool for over one hundred years. And while new geographical maps started to be constructed by the erudite, using the coordinates and prescriptions given by Ptolemy some thirteen centuries before, charts continued to be made by artisans, on the basis of navigational data collected by pilots. Despite being a unique achievement in the history of cartography, if not in the history of civilization, the creation of the medieval portolan chart was still poorly understood at the turn of the twentieth century. With the introduction of new research tools and a deeper study of the extant sources, we have now reached a situation where the initial state of perplexity concerning the very emergence of the portolan charts has given way to a broad consensus about some central questions. The purpose of this article is to appraise the present state of knowledge regarding the so-called ‘origins problem’.