Studying Maps at Scale: A Digital Investigation of Cartography and the Evolution of Figuration
This aim of this thesis is to develop methods and create datasets to investigate cartographic heritage on a large scale and from a cultural perspective. In recent years, heritage institutions worldwide have digitized more than one million maps. Specific techniques have been developed for the automated recognition and extraction of map image content, opening new avenues in historical geographic research. However, thus far, these methods have engaged little with the view that maps are cultural objects, or with the history of cartography itself. Recognizing maps as cultural objects implies that they are not objective, undistorted records of territory but purposeful representations affected by political, epistemic, and artistic expectations. Moreover, cartography functions as a semantic-symbolic system that relies on cultural conventions evolving over time. This work leverages a large, diverse corpus comprising 771,561 map records and 99,715 digitized images, aggregated from 38 digital catalogs across 11 countries. After normalization, the dataset includes 236,925 distinct contributorsâ mapmakers or publishersâ and spans six centuries, from 1492 to 1948. These extensive data make it possible to chart and visualize the geographic structures and global chronology of map publication. In addition, the spatial focus of cartography on particular regions is analyzed in relation to political dynamics, evidencing a conjunctural relationship between Atlantic maritime charting, the triangular trade, and colonial expansion. Further results document the historical progression of national, domestic focus and the impact of military conflicts on publication volumes. The present research also introduces state-of-the-art semantic segmentation techniques and detection models for the generic recognition of land classes and cartographic signs. The training relies on dedicated sets of annotated data, augmented with synthetic images, for segmentation. The analysis of semantic land classesâ such as buildings, water, and roadsâ shows that maps are designed images: framing and composition emphasize particular geographic features through centering and semantic symmetries. The study of cartographic figuration relies on the encoding of 63 million signsâ such as icons and symbolsâ and 25 million fragmentsâ depicting texture, linework, and colorâ into a visual, latent space. The distribution of signs and fragments across periods reveals moments of rupture, denoting figurative shifts, like the replacement of relief hachures by terrain contours. Despite a trend toward diversification, signs tend to form locally consistent, univocal systems. The analysis of social transmission through collaboration underscores the influence of legitimacy and the role of larger actors in the emergence of figurative norms. Finally, models of diffusion across publication centers show that larger cities tend to develop distinctive, differentiated semiotic cultures and function as transmission hubs. To conclude, this thesis presents large datasets and computational methodologies to study the influence of political power, technological change, semiotic constraints and cultural transmission on the evolution of cartography.
École Polytechnique Fédérale de Lausanne
Prof. Jérôme Baudry (président) ; Prof. Frédéric Kaplan, Dr Isabella Di Lenardo (directeurs) ; Dr Mathieu Salzmann, Prof. Leif Isaksen, Prof. Stefan Leyk (rapporteurs)
2025
Lausanne
2025-10-31
11559
397