When history leaves a mark: a new measure of Roman roads

It has been twenty years since a new literature emerged. Nunn (2009) and three volumes edited by Michalopoulos and Papaioannou (2017) represent the most complete surveys on this 'new economic history' literature. In recent years empirical works on the persistence of history multiplied. If the 'new economic history' literature has no hesitation in confirming the long-term effect of history, some recent contributions reveal that this persistence does not always occur. By inserting into this framework, the paper has a twofold aim. First, it provides an alternative summary of this literature, collecting those contributions that do not retrieve in history an important factor explaining current economic results. On the other hand, starting from the huge amount of works that confirm the persistence of historical facts, it focuses on those contributions that find in the old transport infrastructure the link between past and present. In last five years, the historical Roman road network has assumed a leading role in this field. And by reviewing the original works that focus on the long- lasting effect of the Roman domination and infrastructure, this paper introduces a new measure of Roman roads that has been constructed at the Italian NUTS3 level. The measure computes the length in kilometers of Roman roads for each province in Italy, and contributes to the literature on historical infrastructures, providing a new precise measure to use for empirical purposes, easy to extend at the regional or at the country level and simple to replicate in all those territories where Roman roads have been constructed.