From the Adriatic to the Alps: an examination of inland trade in Northern Italy between the First Century BC and Fifth Century AD

Abstract

Within the Italian peninsula, Northern Italy has previously been maligned as a marginal and unimportant inland region during the Roman era. Inland areas are assumed to have been difficult to access, with long-distance trade dropping off as distance from the coast increased. Although the presence of a navigable river might extend the reach of imports, prevailing orthodoxies continue to suggest areas furthest away from the coast had less access to overseas goods. Long-distance trade between coastal regions has been the subject of intensive study by Roman archaeologists for the past thirty years, but the complex dynamics that governed inland trade have not seen the same level of interest. Within this thesis, Northern Italy serves as a case study to explore the role transport cost and consumer choice played in the distribution of local and imported goods throughout inland regions during the Roman period, moving beyond simple models of marginality and isolation.

The thesis uses a combination of route network modelling and quantitative statistical analysis to study patterns of inland trade between the first century BC to the fifth century AD. Two network models, one mapping the cost and time of transporting ‘standard’ cargoes, the other mapping the cost and time of transporting ‘heavy’ cargoes, are examined. Containing over 136 nodes, they enable a significantly more detailed analysis of Northern Italy’s transport network than previous modelling. The results of the network analysis are compared against the geographical and chronological distribution of material data from 37 urban sites across the region. Three material datasets of amphorae, red-slipped finewares, and decorative stone are statistically analysed using a combination of hierarchical clustering, based on assemblage provenance, and diversity indices (Simpson’s Index and the Morisita-Horn Overlap Coefficient), utilising the individual vessels and lithotypes present within the datasets.

The results of the analysis show that inland trade in the Roman period was far more complex than a simple regression of imports as distance from the coast increased. Clear zones of consumption across Northern Italy are seen in the distribution of the material data, closely linked to transport costs. The Po river network is shown to have been crucial in facilitating long-distance trade from the coast to inland regions, but the results also reveal that the significance of trans-mountain trade in supplying parts of Northern Italy with staple goods has been underestimated. Areas furthest inland are often shown to have had the greatest diversity in the provenance and types of material in their assemblages, as opposed to coastal areas, which demonstrate more limited provenances and greater uniformity. The results highlight the complex array of factors governing inland trade, alongside the interplay between cost and choice in the decisions made by consumers. Far from being a disconnected and isolated inland region, the Po valley and Northern Italy more generally is shown to have been connected to wider Eastern and Western Mediterranean markets and networks of information.