As a continuation of the Bernese research project on the development of Ptolemy’s catalogue of localities, this dissertation investigated the Iberian peninsula in Ptolemy’s Geography.



By comparing present-day locations with the Ptolemy’s coordinates, certain characteristic differences become apparent; these differences have been used to identify sources and methods used by Ptolemy to determine geographical coordinates. It was possible to show that Ptolemy used mainly geometrical methods to build his map, based on geographical information (distances, latitudes) that also passed down in other antique works such as Strabo’s Geography or Pliny the Elder’s Natural History. Moreover, the analysis of Ptolemy’s method enabled to shed light on the transmission history of the Geography: one of the two main recensions of the catalogue appears to have underwent significant modifications, providing new elements to sharpen our philological approach of Ptolemy’s Geography.

This Ph.D. thesis was part of the program “History of Ancient Science” (HistAS) of the Berlin Graduate School of Ancient Studies (BerGSAS) and was successfully completed in 2016.


Olivier Defaux, The Iberian Peninsula in Ptolemy’s Geography. Origins of the Coordinates and Textual History, Berlin: Edition Topoi, 2017