Trade in the Roman Empire: A Study of the Institutional Framework Taco T. Terpstra Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in the Graduate School of Arts and Sciences COLUMBIA UNIVERSITY 2011 © 2011 Taco Terpstra All Rights Reserved ABSTRACT Trade in the Roman Empire: A Study of the Institutional Framework Taco Terpstra The leading question behind this dissertation is: how did trade operate in the Roman Empire under conditions of imperfect government enforcement in private contracting, and of imperfect information? The Roman State, unlike modern states, did not employ the powers at its disposal to enforce private contracts made under the rules of its legal system. Given the lack of government support, information on merchants’ reliability and trustworthiness was extremely important in conducting long-distance trade. However, under pre-industrial conditions information could only travel slowly, making it difficult for merchants to assess risk. This dissertation offers a micro-economic model of how these problems were solved in the Roman Empire. It argues that information circulated within networks defined by geographical origin, with the loss of one’s reputation or trading position within those networks forming the instrument of enforcement. The discussion consists of three main parts: intra- community trade in the Italian harbor-city of Puteoli; inter-community trade between the provinces and Puteoli, Ostia, and Rome; and finally inter-community trade between Italian merchants and the provinces. Introduction 1 I. Intra-community exchange and the use of law in Puteoli Intra-community exchange in Puteoli 8 The Murecine tablets: archive and archaeology 11 Commerce and social standing in ancient Puteoli 16 Reputation-based versus law-based institutions 26 Path dependence: ‘history matters’ 36 Path dependence: ‘sunk’ organizational capital 43 Path dependence: satisfactory outcomes 51 Conclusion 57 II. The role of trading stations in overseas exchange in Puteoli Intra- and inter-community trade 60 Inter-community exchange and the debate on the Roman economy 63 Medieval inter-city trade 66 Individual legal responsibility; the Murecine tablets 71 A micro-economic model of long-distance exchange 78 The Tyrian trading station 84 Tyrian agents as a trading ‘bridge’ 94 Overseas agency as a general system of exchange in Puteoli 101 Conclusion 112 i III. Coalitions of foreign merchants and shipowners in Ostia The Maghribis’ coalition and medieval trade 115 Comparing the Maghribis and trade networks in the Roman Empire 119 The Ostian material evidence: the ‘piazzale delle corporazioni’ 121 Settlers from overseas living in Ostia 140 Conclusion 149 IV. Overseas trade and the city of Rome Orbis in urbe 152 Stationes on the Forum Iulium 156 Stationes on the Sacra Via 164 Ephesians in Rome 178 Palmyrenes in Rome 183 Syrians in Rome 194 The western provinces and Africa 199 Conclusion 203 V. Roman traders in the province of Asia The Roman East as a case-study 208 Law and life of Asia 216 Romans resident in Ephesus 236 Romans resident in Magnesia and Tralles 240 Romans resident in Apamea 248 ii The Roman settlers’ social position 253 Conclusion 269 Conclusion 272 Abbreviations & Bibliography 276 List of illustrations Fig. 1 ‘Piazzale delle corporazioni’ 151 Fig. 2 Forum Iulium with Clivus Argentarius 206 Fig. 3 Forum Iulium, Imperial fora, and Sacra Via 206 Fig. 4 Stationes on the Sacra Via 207 Fig. 5 Roman Asia Minor 271 iii Acknowledgements In the course of writing this dissertation I have incurred many debts of gratitude. First and foremost I am deeply indebted to my academic advisors, William Harris and Roger Bagnall, who over the years have provided me with essential guidance, comments, and criticism. During my seven years in Graduate School, their mentorship has been a constant reminder to me just how lucky and privileged I was, working with scholars and mentors of their stature. A number of people have contributed to this work with enthusiastic and critical comments. I would like to thank in particular: Justin Dombrowski, Emily Holt, Willem Jongman, Marco Maiuro, David Ratzan, Peter Temin, and Arjan Zuiderhoek. All of them have read parts or all of the manuscript and have provided me with valuable feedback. My deep gratitude also goes to the two dissertation committee members not so far mentioned: Adam Kosto and Ronald Findlay. I am very thankful to both for lending me their expertise; my dissertation is much the better for it. I would further like to express my gratitude to Columbia University for providing me with a Thompson Fellowship for research at the American Academy in Rome during the academic year 2008/2009. I would not have been able to write the third and fourth chapters of this dissertation as they now stand without this generous support. I would also like to thank Columbia’s Center for the Ancient Mediterranean for providing me with the opportunity to visit Turkey’s west coast during the Center’s field-trip in June 2008. The knowledge acquired on this trip has been of great help to me in writing chapter five. Finally I would like to thank my parents who, throughout my time in Graduate School, have been unwavering in their support for me. Their encouragement has been crucial; their sense of pride has been heartwarming. This dissertation is dedicated to them. New York, April 2011 iv Voor P&M v 1 Introduction This dissertation investigates Roman trade, more specifically – as the subtitle indicates – the institutional framework of Roman trade. Abstract though that may sound, the problems addressed are really very down-to-earth and concrete. The leading question behind the whole work can be summed up in a single sentence: how did trade operate in the Roman Empire under conditions of imperfect government enforcement and imperfect information? In the course of this dissertation I will elaborate further on this question, but let me here briefly explain what I mean. The Roman State commanded awe-inspiring powers of physical violence, and did not shy away from using them. However, unlike modern states it did not employ the powers at its disposal to enforce private contracts drawn up by ordinary individuals. The Roman legal system, in that sense, can be said to have been ‘imperfect’. A party to a contract confronted with a default could not call upon the help of the Roman authorities to make a contractual partner honor his obligations. Of course, he could take a defaulter to court, but even with a favorable verdict in hand the vindicated litigant was still pretty much on his own. Ordinarily, no police or military unit would have been available to back him up in putting the court’s ruling into effect. This is not to say that such help will never have been granted. There will doubtless have been instances where the Roman administration – central or provincial – for whatever reason thought it expedient to lend some muscle to an individual litigant. But the point here is that any such help would have been random and arbitrary; it could not be relied upon. Government enforcement simply did not form part of the Roman legal institution in the way it forms part of the legal institution of, for instance, the United States. 2 Since the lightning-fast means of communication we take for granted were unavailable to the Romans, information could only move as fast as sails and legs would allow. The slowness with which information traveled formed a serious constraint on overseas business, a constraint felt increasingly with growing distance. For anyone intending to enter into a transaction with someone in a far-away place it was difficult to assess risk; the data were few, and evaluating their accuracy was a slow and challenging task. How, then, was Empire-wide trade conducted if merchants could not count on third-party enforcement of their contracts, and could not easily gather information on trading conditions in overseas locales? This dissertation offers a model of how such trade operated. Put in the briefest of terms, the argument put forward is that information circulated within small but far-reaching groups defined by origin, with loss of reputation or trading position within those groups forming the instrument of enforcement. In broad outline, the discussion moves geographically outward from the imperial center, consisting of three main parts. The first looks at trade at an intra-community level in a city at the very heart of the Empire: Puteoli (chapter 1). Within a relatively small community, information will have been readily available, although government enforcement was still lacking. I will argue that in the Puteolan community, Roman law was the default mode for economic interaction and conflict resolution, a situation that was the result of a ‘path-dependent’ process; the rules of the Roman imperial legal system had become deeply imbedded as a social convention, creating further behavior that conformed to that particular convention. The ‘embeddedness’ of the rules ensured that they would be followed continuously, in effect ensuring enforcement of private contracts. The second part brings the wider world outside Italy into the discussion, focusing on long-distance inter-community trade. The goal of this second part is to study how traders from 3 the provinces managed to do business in Italian cities. Chapter 2 builds on the findings from the first chapter, analyzing how merchants from other communities managed to trade in Puteoli. It will argue that exchange was conducted through local ‘colonies’ of immigrant merchants domiciled permanently in the city. Chapter 3 then addresses the question how long-distance trading networks operated internally, and how behavior was regulated within them. The chapter takes Ostia as an example, considering most of all the evidence from the so-called ‘piazzale delle corporazioni’.