Introduction

Agricultural wealth played a crucial role in the social and political structure of the Roman Empire. The elite classes that ruled the empire, including the emperor and the imperial family, the senatorial and equestrian orders, and the curial classes in the empire’s many cities, depended on the production of their estates for the revenues that maintained their social and political privileges. The elite’s share of the Roman agrarian economy was considerable, and it is likely that it only increased during the first three centuries CE as the aristocracy was increasingly recruited from across the empire as a whole instead of exclusively from Italy (Duncan-Jones 1990: 121-42; Hopkins 1995/6). We can appreciate the enormous disparities in agricultural wealth by comparing the fortunes of the empire’s wealthier landowners with those of more modest landowners. The Roman senator Pliny the Younger (c.61-113), whose published correspondence includes a great deal of information about the financial concerns of upper-class Romans, owned estates worth perhaps 15-17 million sesterces (Duncan-Jones 1982: 17-32). This figure represents a multiple of the minimum property qualifications for senators and equestrians set by Augustus, which were one million and 400,000 sesterces, respectively. The minimum census requirement for members of the councils in many cities in Italy and the provinces was 100,000 sesterces. At the same time, Pliny’s fortune was dwarfed by those of the very wealthiest members of the Roman elite, which were measured in hundreds of millions of sesterces. To put these levels of wealth in perspective, the census qualification for Egyptian villagers in the early empire on whom the duty to perform public liturgies fell might be at most the equivalent of a few thousand sesterces. The annual pay of a legionary soldier at the time of Augustus was 900 sesterces.

As great as the fortunes of wealthy private individuals were, the state was by far the largest landowner in the Roman Empire. The imperial government derived substantial revenues from state-owned land, or imperial estates, which were to be found in

Italy and in all the provinces. These estates came into imperial ownership from a variety of sources, including bequests to the emperor by grateful senators, the defaulting of property to the state when people died without heirs, and the confiscation of property of those unfortunate enough to be condemned for capital crimes or for tax arrears. The revenues from imperial estates played a crucial role in the public programs supported by the Roman government, and they supplemented the revenues that the state gained from taxes imposed on privately held land. Thus revenues from imperial estates in North Africa provided wheat and later olive oil to the programs in Rome that distributed these products to the urban populace. In Egypt, the state arranged for the shipment of grain collected as taxes from private land and as rents from state-owned land down the Nile to Alexandria, from where it was shipped to Rome or to other cities in the east. Other social programs sponsored by the imperial government and private benefactors also revolved around agricultural production. For example, to fund alimentary foundations in Italian cities, the state lent sums of money to participating landowners based on the size of their holdings. The interest paid by these landowners provided funds to support the raising of children.

The substantial stratification of wealth and the social and political privileges that the elite enjoyed raise a basic question about the nature of the Roman agrarian economy. Was this economy completely dominated by a landowning elite, with the vast majority of the empire’s wealth subject to the control of powerful landowners, or did the Roman economy also provide opportunities to a broader range of people to prosper from agriculture? The development of the imperial peace created enormous opportunities for Roman estate owners to make profits by supplying agricultural products to the growing urban population in the empire. Indeed, the archaeological evidence for olive and wine presses indicates that landowners in many parts of the empire, in particular in Spain and Africa, invested heavily in the production of wine and olive oil, which could be sold as a cash crop to supply not just Rome but cities in the provinces as well (Peacock and Williams 1986: 54-66; D. J. Mattingly 1988c). At the same time, we should not overestimate the economic power of the Roman elite. In a largely agrarian economy, elite Roman landowners lacked the freedom of choice in investing their wealth that we might associate with a modern, market economy. Investment in agriculture represented the preeminent form of financial security for upper-class Romans, a source of income that could be expected to be stable over the long term and that also carried social prestige (Veyne 1979). In light of this fact, the strategies that Roman landowners adopted in managing their agricultural wealth are likely to have been very conservative, aimed at preserving wealth and maintaining their social privileges. Such a conservative strategy had important implications for the relationships between Roman landowners and other small farmers - in particular, the tenants who cultivated much of their land. Many upper-class landowners, then, sought to avoid risk and contented themselves with an income generated from the production of their tenants. The incomes of such landowners depended not so much on their ability to adjust their investment strategies to changing market conditions as on their ability to capture some of the surplus production of their tenants (Horden and Purcell 2000: 231-97, esp. 245).

Environmental and technological constraints limited the productivity of Roman agriculture. Agriculture in the Roman Empire tended to be extensive, since farmers had little capacity to apply fertilizer or other inputs to raise the productivity of the land. In many parts of the Roman world, farmers used the two-field system, often called ‘‘dry-farming,’’ to cultivate wheat. Adapting to the hot and dry summers and rainy winters of the Mediterranean climate, farmers would repeatedly plow the land to preserve moisture, sowing the crop in the fall, and after harvesting it in the spring, letting the land lie fallow for one year (Grigg 1974: 123-51). Yields under such conditions are likely to have been modest, on the order of about 500 kg/ha, a figure that would be on the low end of yields attested in medieval Italy (Spurr 1986: 82-8). To increase the production of their land, farmers could engage in polyculture, which involved the cultivation of grain in combination with tree crops such as vines or olives (Horden and Purcell 2000: 209-20; Sallares 1991: 304-9). Many farmers supplemented their incomes by raising livestock, especially sheep for wool and also for meat (Horden and Purcell 2000: 197-200). But the shortage of pasture often meant that livestock had to be kept away from the cultivated area, which deprived farmers of the use of their livestock’s dung, which was the most common source of fertilizer. In areas without annual precipitation of 300-400 millimeters, irrigation would be required to cultivate wheat and other crops (Horden and Purcell 2000: 237-57). In arid regions of Africa, for example, irrigation involved capturing the water from occasional violent rainfall to cultivate crops in terraces dug out of hillsides, or tapping springs to water olive trees (B. D. Shaw 1982, 1984b).