Computer modelling and simulations have become common in social and natural sciences, but classical studies seem slightly reluctant in accepting them as standard working tools. Although they are gradually becoming more appreciated in ancient history research (e.g. T. Brughmans, J. Poblome, ‘Roman Bazaar or Market Economy? Explaining Tableware Distributions through Computational Modelling’, Antiquity 90 [2016], 393–408; T. Brughmans, A. Pecci, ‘An Inconvenient Truth. Evaluating the Impact of Amphora Reuse through Computational Simulation Modelling’, in: A. Bowman and A. Wilson [edd.], Recycling and Reuse in the Roman Economy [2020], pp. 191–237; S.A. Crabtree, ‘Simulating Littoral Trade: Modeling the Trade of Wine in the Bronze to Iron Age Transition in Southern France’, Land 5 [2016]; I. Romanowska, ‘Using Agent-Based Modelling to Infer Economic Processes in the Past’, in: J. Remesal Rodríguez et al. [edd.], Cuantificar las economías antiguas: Problemas y métodos [2018], pp. 107–18; I. Romanowska et al., ‘A Study of the Centuries-Long Reliance on Local Ceramics in Jerash through Full Quantification and Simulation’, Journal of Archaeological Method and Theory 29 [2022], 31–49), there are still many doubts regarding their value and proper use, which most probably result from a lack of understanding of what these models represent and from a fear of what is beyond simulations based on complicated codes (A. Van Oyen, ‘Agents and Commodities: a Response to Brughmans and Poblome (2016) on Modelling the Roman Economy’, Antiquity 91 [2017], 1356–63) that for multiple representatives of humanities appear to come from the ‘dark arts’ environment. The volume under review clarifies many of these doubts and shows the usefulness of various types of simulations and computer models in the study of the economic history of ancient Rome.
The volume is composed of twelve chapters, authored by an international cohort of archaeologists and ancient historians, experienced in both theoretical and practical aspects of computer modelling and simulations. It starts with a comprehensive introductory chapter by Brughmans that describes the idea and purpose of computer simulations in ancient studies and explains how we can simulate the economy. This part is followed by ten case studies, regarding five aspects of the Roman economy:
1. Transport systems and infrastructure (Chapter 2: ‘Simulating Roman Maritime Trade: Modelling Sailing Times and Shipping Routes’, P. Warnking; Chapter 8: ‘The Economic and Social Evolution of the Iberian Peninsula as Revealed through Analysis of Roman Transport Infrastructure’, P. de Soto and C. Carreras; Chapter 9: ‘Evaluating Hypotheses about Local Transport Systems through Spatial and Network Analysis: the Dutch Part of the Lower Rhine Limes and its Hinterland’, M. Groenhuijzen);
2. Demography and the role of epidemics (Chapter 3: ‘The Antonine Plague: a Case Study of Epidemiological Modelling and Impact Evaluation’, M. Vlach; Chapter 10: ‘Modelling the Basics of Roman Demography: the Case of the Dutch Limes’, P. Verhagen);
3. Urbanisation and settlement network (Chapter 4: ‘Settlement Scale and Economic Networks in the Roman Empire’, J.W. Hanson and Brughmans);
4. Commercial exchange and cultural transmissions (Chapter 5: ‘Transmission of Cultural and Economic Strategies in Inter-Regional Tableware Trade’, S. Carrignon, Brughmans and I. Romanowska; Chapter 6: ‘New Approaches to Old Questions: the Exploration of Large-Scale Trade Dynamics using Hypothesis-Testing Frameworks’, X. Rubio-Campillo and M. Coto-Sarmiento; Chapter 11: ‘Mapping the Landscape of our Ignorance’, S. Graham);
5. Agricultural production and its distribution (Chapter 7: ‘A Model of Grain Production and Trade in the Roman World’, B. Dermody, A. Chiu-Smit and R.L.P.H. van Beek).
The book ends with a detailed summary and conclusions by Wilson (Chapter 12). This volume is therefore the first robust and comprehensive guide to the application of computer modelling and simulations to the study of both general and case-specific aspects of ancient economic history, which helps non-specialists to understand this innovative approach by using diversified case studies, various types of evidence (both archaeological and historical) and non-technical language. It differs from many other books published within the series Oxford Studies on the Roman Economy by not having a common topic (like trade or agriculture in the Roman economy), but a common method – different ways of modelling and simulating ancient economic reality.
The computational models and simulations presented in the volume include statistical tests such as Null Hypothesis Significance Testing (NHST) and Bayesian modelling (Chapter 6), Expedition software model of Roman maritime trade, which can be compared with the more detailed ORBIS (https://orbis.stanford.edu) (Chapter 2), and a model of grain production and distribution that combines climate and hydrological data (NCEP/NCAR and PCR-GLOBWB respectively) with the ORBIS network (Chapter 7). Network analyses are represented by two chapters (Chapter 8 and 9), while five (3, 4, 5, 10 and 11) concentrate on agent-based modelling (ABM) and the use of NetLogo environment for simulations.
The collection addresses an immensely complex and pivotal issue of Roman economic performance, which has long been a source of vivid scientific disputes. The case studies substantially contribute to our knowledge of the ancient economy seen from an interdisciplinary perspective. They acknowledge the high complexity of the Roman economy; but instead of traditional examinations of textual and material sources against or in support of theoretical models, they offer formal representations of different models and hypotheses. Furthermore, they show the potential of databases of archaeological material – quantitative analyses combined with computer simulations are perfect ways to overcome the problems regarding incompatibility of different datasets and the incompleteness of archaeological data. The publication follows the path set by Finding the Limits of the Limes. Modelling Demography, Economy and Transport on the Edge of the Roman Empire (2019), edited by P. Verhagen, J. Joyce and M.R. Groenhuijzen (a couple of chapters touch upon similar subjects and simulations/models, though in a more developed version, e.g. Chapter 8 by de Soto, 9 by Groenhuijzen and 10 by Verhagen). In terms of approach to the economy and the use of proxy data the volume complements Complexity Economics: Building a New Approach to Ancient Economic History (2021), edited by K. Verboven. On the other hand, by modelling and simulations of various aspects of ancient reality with the use of network analyses it supplements Maritime Networks in the Ancient Mediterranean World (2018), edited by J. Leidwanger and C. Knappett.
The volume would benefit from demonstrating new paths for future models and simulations, such as new or reframed theories or perspectives towards economic practices or types of evidence/databases of archaeological material that could have been considered (new approaches and categories of evidence can be found in: Reframing the Roman Economy. New Perspectives on Habitual Economic Practices [2022], edited by D. Van Limbergen, A. Hoffelinck and D. Taelman). It may surprise readers that the presented models and simulations still oscillate around two theoretical alternatives: the bazaar model of P. Bang (The Roman Bazaar: A Comparative Study of Trade and Markets in a Tributary Empire [2008]) and the market model of P. Temin (The Roman Market Economy [2013]), without proposing any ‘middle ground’. What also seems to be missing in the volume, especially in the discussion part, is a critical evaluation of models and simulations in terms of their correctness and validity (some issues are mentioned in Chapter 11, but this is not a comprehensive critique). This is particularly important considering that, by necessity, the complicated code that is hidden behind graphic representations is obviously missing in all publications and cannot be verified by an average scientist, which is particularly important when one command can utterly change the results. Moreover, models and simulations simplify a highly complex and dynamic economic system of the ancient Roman Empire, composed of a number of variables and not always predictable elements interconnected through different kinds of relationships, to epithets like ‘high’, ‘moderate’, ‘low’ etc., which poses a risk of drawing over-simplistic conclusions and overlooking nuances of ancient economic reality.
The book’s audience and success could have been much wider if more appendices were added to each chapter with information on how certain economic processes and phenomena were defined and codified and which programmes/environments were used in order to run simulations (links to websites would have been welcome). Finally, it seems that no particular effort has been taken to organise the case study chapters, as they are presented with little order (organised neither according to a method nor a subject). Regrettably, this sometimes makes it difficult to follow properly the thread of the publication, but these flaws are of a technical rather than a substantive nature.
Despite these minor caveats, it should be emphasised that the volume is a valuable entry in the debate on Roman economic performance. It offers ample ground and inspiration for future research in Roman economic history and ancient history in general, demonstrating the potential of computer models and simulations in constructively enhancing research processes and providing new insights that cannot be obtained by traditional approaches. It is likely to set a new trend in ancient studies, encouraging more simulations in different research areas (not only the Roman economy), such as transmission of cultural behaviours, religious ideologies or appearances of political powers. A coherent introduction, which clearly states why, where and when we need computer simulations and modellings, together with various case studies, diversified in time, space and aspects of economic behaviour, familiarise non-specialists with the subject. Fittingly illustrated with lucid maps and graphs the volume opens new methodological paths in ancient history studies. By careful examination of archaeological material and comparison with simulation results the book provides new, sometimes unexpected answers to old questions, which develop our understanding of the Roman economy.Footnote 1
