Diachronic analysis of the growth of the French railway network between 1860 and 1930: connectionist expansion and hierarchical selection?

The emergence of the railways in France in the 19th century extended spatial and temporal horizons, creating a major disruption in accessibility. Although railway infrastructure spread widely in its growth phase throughout the country between 1860 and 1930, the ‘speed revolution’ made possible by the train was not homogeneous. This paper questions these two dimensions of the French railway network using a geohistorical and quantitative approach. Our aim is to show the impact of hierarchical selection processes in the shaping of the network, according to spatial and temporal perspectives. To this end, we use graph frameworks based on the French RAilway NEtwork (FRANcE) database which contains information on the spatial extension of the network and average speeds of network sections. We use graph theory to identify universal principles of network science and study their territorial inscription. These results retrace the development of the railway, showing that the most dynamic urban centres gained access first, and identifying the network’s sometimes surprising structuring axes and the gradual establishment of sub-networks. This study contributes to the construction of a research instrument exploring socio-economic changes according to adaptive spatio-temporal scales.