It's all in the Mail: The Economic Geography of the German Empire

Information exchange is a necessary prerequisite for economic exchange over space. This relationship implies that information exchange data corresponds to the location of economic activity and therefore also of population. Building on this relationship we use postal data to analyse the spatial structure of the population distribution in the German Empire of 1871. In particular we utilize local volume data of a number of postal information transmission services and a New Economic Geography model to create two index measures, Information Intensity and Amenity. These variables respectively influence the two mechanisms behind the urban population distribution, namely agglomeration forces and location endowments. By testing the influence of actual location characteristics on these indices we identify which location factors mattered for the population distribution and show that a number of characteristics worked through both mechanisms. The model is then used to determine counterfactual population distributions, which demonstrate the relative importance of particular factors, most notably the railroad whose removal shows a 34% lower urban population. A data set of large locations for the years 1877 to 1895 shows that market access increases drove the magnitude of the increase in urban population, while endowment changes shaped their relative pattern.