Hadrian, Middlemen and the Exploitation of Imperial Domains

Abstract

The size of the patrimonium Caesaris made it impossible for emperors to manage their properties in the way private aristocrats could. Agents and middlemen were inevitable. The extension and the administrative complexity of the patrimonium meant that the emperor had to rely on multiple agents with potentially divergent interests to obtain the information needed to make decisions, and to communicate, and enforce them. Our sources reveal contractors, equestrian officials and members of the familia Caesaris charged with the administration and exploitation of imperial estates around the empire. Scholars identify three main models of exploitation: direct management by slaves, subdivision among tenants under the control of a procurator (one-tier tenancy), and two-tier tenancy with larger-scale conductores and smaller-scale tenants. Initially, practical constraints and a desire to maintain local traditions determined which system was chosen. Agency theory, however, allows a better appreciation of the efficiency of each model. It shows that the model of one-tier tenancy supervised by a procurator corresponds best to the efficient distribution of residual risks and decision functions found in modern complex organizations. It is probably no coincidence, therefore, that this model is most frequently found in our sources and appears to be one into which less efficient solutions gradually evolved. A partial transition from two- to one-tier tenancy is documented in the agrarian inscriptions of the Bagradas Valley in Africa Proconsularis. A new reading of the final lines of the sermo procuratorum shows that Hadrian’s administration had been willing to bypass the conductores and abandon two-tier tenancy even for the saltus of the Bagradas Valley for new plots brought under cultivation under the terms of the lex Hadriana and on which the coloni had decided to farm grain. High transaction costs for gathering information and enforcing decisions also explain optimization efforts by the imperial administration. Better archiving practices of the patrimonium in Italy and in the provinces enabled the wider shift toward one-tier tenancy with fixed rents calculated on the productivity of each fundus. The dossier of the Bagradas Valley shows that the lex Hadriana was introduced probably after decades of punctual answers to single petitions. Its wide publication ensured that tenants were aware of their new rights and promoted the effectiveness of decision enforcement. New incentives/disincentives for the conductores to induce a more cooperative attitude from their part also contributed to the reduction of transaction costs. Our fragmented documentation rarely allows the identification of actual decision-making processes at the central level, in which the emperor and his advisors were involved. NIE helps to take into account all the costs surrounding the decisions taken in Rome about the patrimonium Caesaris, and this is a valuable contribution to our understanding of what sort of landowner the emperor was.