There can hardly be any doubt that goods moved in large quantities and over great distances under the Roman empire. This awareness is borne out of a long tradition of archaeological research attesting to the widespread distribution of specific categories of material culture across the full expanse of the Mediterranean and beyond. This phenomenon has been interpreted as a more or less direct result of Rome's military expansion and the fundamental political unification which came with it, bringing about unprecedented conditions which favoured trade and exchange. Scholarship has often stressed the rôle played in this by ‘institutions’: the spread and adoption of a common set of laws, currency and units of measure, fostered by a relatively long period of internal peace and political stability, would have boosted the economic performance of the empire to levels that had not been witnessed before and would not be seen again for many centuries. Indeed, the notion of ‘efflorescence’ has sometimes been employed to describe and explain the kind of economic growth to which this process might have contributed.