GeoHistoricalData

From the main site of http://geohistoricaldata.org/

Our group gathers about twenty researchers around a project with two fundamental and distinct goals that we believe important to keep connected in order to: study territorial evolutions at different scales or levels (from the cadastral parcel to the national territory), build tools to accurately and flexibly answer such questions. For these reasons, we started a large project to collaboratively digitize several maps of the city of Paris and of France from the 18th century to the 20th century. The digitization of historical sources is usually done locally by researchers for the immediate needs of their research without sharing their work and results with others. We believe it is essential to build a shared platform not only to work together but also to have a collective control over the production process of the data, their transformations and their analysis. Operations such as scanning, georeferencing and digitization of historical sources imply several and delicate choices. These choices should be documentated and tracked.

Reducing the deformations of historical sources during georeferencing usually implies geometric displacements between consecutive maps. Our approach consists in taking theses displacements into account after the digitization process using data conflation / matching tools. Such tools should allow researchers to control and take into account the imperfections of the data throughout their analysis. Furthermore, opendata and open source tools provide the scientific community with the ability to control, track and reproduce the results at every stage.

Datasets

Paris and its suburbs from 1789 to 1950

France from 1747 to 1950