WHIRLWIND OF NUMBERS — DEMOGRAPHIC EXPERIMENTS FOR ROMAN CORINTH* Abstract: The reconstruction of population-levels for ancient cities is a difficult undertaking. Many methods are present in the literature, each with their own (dis)advantages. This paper presents an illustration on the methodological issues encountered in the reconstruction of the popula- tion-levels of an ancient city. The city of Corinth is used as an example, since it has a long history of scholarly interest (including demographic) and it is considered to have played a pivotal role in Roman Greece. Excavations at the site of Corinth have revealed a strongly monumental- ized site which seems to at least equal its Greek predecessor. In terms of population, Corinth has been estimated as one of the larger cities in Roman Greece. Corinth is therefore a focal point of academic attention for researchers both directly and indirectly involved in its studies. 1. CORINTH, POPULATION AND FOOD Estimations of population-size and food production in Antiquity are problematic due to the lack of accurate sources and statistics. Various methods have been used to reconstruct these, but it remains a matter of intelligent speculation. An illustration on the methodological issues encountered in such an exercise is presented in this paper. The figures which result from these calculations and deliberations are estimates, relying on imperfect data. The city of Corinth is used as an example, since it has a long history of scholarly interest (including demographic) and it is considered to have played a pivotal role in Roman Greece. Engels’s volume Roman Corinth: an Alternative for the Classical City argued that Roman Corinth was a service city, i.e. a city that was able to flourish by provisioning a variety of services to visitors of all kinds. The full implications of the book become problematic upon investigation: most of the food for the inhabitants had to be imported via service-provision to visitors1 or via tax-tribute from neighbouring towns. The discrepancy * This study of Roman Corinth derived from my MA-thesis entitled Feeding Roman Corinth: an Exploration in Urbanism, Economy and Population Sustainability, Leiden University, 9th of May 2007. I express my gratitude to John Bintliff and David Gilman Romano for reading and discussing the draft. I also wish to thank Patrick Degryse and Maarten Loopmans for their helpful comments, and Jeanette Marchand for her insight on Kleonai. I am also indebted to Jeroen Poblome for his assistance and comments. This paper was written within the framework of the ICRATES project, funded by the Fund for Ancient Society 42, 127-158. doi: 10.2143/AS.42.0.2172291 © 2012 by Ancient Society. All rights reserved. 995510_AncientSociety_42_07.indd5510_AncientSociety_42_07.indd 112727 33/10/12/10/12 009:049:04 128 R. WILLET between production and population is large and the arguments of Engels have been criticized in the past,2 although some studies have used the size derived by Engels as well.3 A reassessment of these figures follows, in order to draw tentative con- clusions on the demography and agricultural sustenance of Roman Corinth. 2. ESTIMATING CORINTH’S AGRICULTURAL POTENTIAL The first issue of sustenance is addressed by establishing the size of the hin- terland and its arable land. The size of the hinterland of Corinth is set here at 865 km2. This is based on the measurements by the work of the Athens Centre of Ekistics, directed by Doxiades, whose topographical survey of the region where Kleonai, Nemea, Isthmia and Corinth where located, using the natural boundaries, resulted in ca. 1000 km2.4 Other figures are present in the studies on Corinth as well, all varying between 800-900 km2.5 The variation in these figures is mostly dependent on measuring methods and the inclusion of Kleonai in the territory.6 At present, it is difficult to confirm an inclusion of the area (pers. comm. J. Marchand) and therefore the area of Kleonai is not included in the territory of Roman Corinth. The next step is to estimate the part of this territory which is arable, i.e. the area of land on which crops could be grown. Again, various fig- ures are available, measuring from 207 km2 (Engels) to ca. 295 km2.7 The latter amount based on the average of two agricultural censuses in the region. The idea that pre-modern agriculture could be (cautiously) compared to the Roman era is also argued by Kron.8 The assumed simi- larities in exploitation systems would allow for a cautious comparison between ancient and traditional farming methods. There need not be a Scientific Research-Flanders, Belgium (G.0788.09 and G.0562.11). The research theme forms part of the framework of the Leuven Centre for Archaeological Sciences, IUAP 6/22, GOA 2007/02 and Methusalem. 1 Engels (1990) 27 & 84. 2 E.g. Saller (1991) 351-357; Spawforth (1992) 119-120; Walbank (1991) 220-221. 3 E.g. Alcock (1993) 162-168. 4 Sakellariou & Faraklas (1971) 3. 5 Beloch (1886) 115; Salmon (1984) 19; Engels (1990) 27; Legon (2004) 466. 6 Walbank (1997) 104; Romano (2003) 299; Marchand (2003); Strabo, 8.6.19 [377] (T229); Plutarch, de sera numinis vindicat 7, T180. 7 Engels (1990) 204; Walbank (1997) 104 — note that the latter figures here are cor- rected to Sakellariou & Faraklas (1971). 8 Kron (2000) 277-287. 995510_AncientSociety_42_07.indd5510_AncientSociety_42_07.indd 112828 33/10/12/10/12 009:049:04 WHIRLWIND OF NUMBERS 129 correlation between these censuses and the actual land-use in antiquity, e.g. in Boeotia the land-use was probably much higher in the Classical period than in the modern period,9 but it does give an indication of the possibilities. The lack of land-use figures for the ancient world and the uncertainties of applying traditional figures as proxy will prevent the calculation of an absolute yield of production for the Corinthia.10 Instead, a safer course is to estimate a maximum production during optimum conditions to create an upper limit. When the measured amounts of arable land are compared to popula- tion censuses from 1907, 1920, and 1961, it does not necessarily follow that these represent the maxima of land-usage. The population of the area was highest in 1961, while the size of agricultural land-use was slightly higher in 1911. Although a maximum of arable land could be obtained by taking the highest measured amount of arable land per region (totaling 433.22 km2), this would ignore the full implications of the figures: i.e. between 1911 and 1961 some 144 km2 of arable land was abandoned, while some 132 km2 of previously unused land was used for agriculture. This raises the question why this change occurred in the agriculture of the 20th century. But it is clear that a maximum of 433.22 km2 is a presumption, which cannot be supported by these figures at this point. Therefore the largest observed figure of 300 km2 is used. Region Arable Fallow or Arable Fallow or Change Max. arable land in uncultivated land in uncultivated in land(sq 1911(sq land in 1961(sq land in amount km) km) 1911(sq km) km) 1961(sq of land km) used (sq km) 1. N.W. 18.76 3.15 2.94 0.86 - 15.82 18.76 corner of Mt. Geraneia 2. Isthmia- 1.16 - 20.39 6.67 + 19.23 20.39 Crommyonia 3. Coastal 76.90 27.41 142.24 31.09 + 65.34 142.24 and Loutraki plains, part of Isthmus 9 Bintliff & Snodgrass (1985) 62. 10 Halstead (2002) 53-70. 995510_AncientSociety_42_07.indd5510_AncientSociety_42_07.indd 112929 33/10/12/10/12 009:049:04 130 R. WILLET 4. Middle 10.18 3.87 35.62 13.79 + 25.44 35.62 and Upper Xerias Valley 5. Solygeia 26.57 5.31 8.35 1.01 - 18.22 26.57 6. Sophiko 114.58 6.96 34.87 3.76 - 79.71 114.58 7. Korphos 31.83 10.06 1.07 - - 30.76 31.83 8. Hagios 3.41 2.00 10.16 1.89 + 6.7510.16 Ioannes 9. Part of 17.19 8.30 33.07 7.15 + 15.8833.07 Kleonai Valley belonging to Corinthia Totals 300.58 km2 67.06 km2 288.71 km2 66.22 km2 433.22 km2 Table 1 — Agricultural censuses of 1911 and 1961 Once the size and arability of the land are approximated, the following step is to convert the amount of arable land into a figure representing the number of people sustained by this land. Engels calculated the amount of barley potentially grown in this area, since barley was a staple good commonly grown in dry areas in antiquity. The total amount of people sustained by the hinterland is achieved by multiplying the amount of arable land with a figure for the yield of barley, which was then divided by the amount of barley needed per person per year11: 207 (area of arable land) * 1,200 (hectoliter yield per km2) * 0.5 (fallowing of the land) = 124,200 hl or 7,675,560 kg (at 61.8 kg/hl) of barley, which at a calorific yield of 2,158 kcal per kg barley and a daily calorific need of 2,600 kcal per person, results in 17,524 people sustained. As a result, 36,124,488 kg of barley needed to be imported to Corinth if the total population of the Corinthia numbered 100,000. Using 300 km2 the land would be able to sustain 25,397 people at maximum capacity. Another model to calcu- late the amount of food produced by the land is provided by Garnsey, who uses both barley and wheat to establish the yield of the land.12 Calcula- tions were made for Attica, for which Garnsey proposes an estimated 17.5 per cent of the land was under grain.