4.1 Settlement distribution
Apart from the carrying capacity of the landscape, the size and composition of the local population determined the amount of food that could have been supplied to the army. The large-scale settlement excavations of recent years have provided a wealth of information on this „topic. However, few settlements have been excavated completely and have been studied in „enough detail to discover the number of farms per settlement and per period. Vos (2009) made an attempt to collect this information for the Kromme Rijn area, which is located in the northwestern part of the Dutch River area, and was part of the civitas Batavorum in the Roman period. The north-western section of the Kromme Rijn area is part of our research area (fig. 2). Vos uses an average number of 2.5 farms per settlement for the Kromme Rijn area (Vos 2009, 215), but argues that there is a differentiation in rural settlements in this part of the Batavian region - in between the rivers Rhine and Lek and bordered in the west by coastal peat - varying from many small settlements of one or several households to a few large settlements with a minimum of four farms and a regional function (Vos 2009, 225-237). It also seems that the number of settlements in this region increased in the first two centuries A.D., combined with a developed in settlement structure. Most of the settlements date to the second/third century.
Still little is known about the rural population in the peat and coastal regions of the research area, which were probably part of the civitas Cananefatium. Only one agrarian settlement, near Katwijk-Zanderij, located in the dunes of the coastal region, has been investigated extensively (Van der Velde 2008). Van der Velde assumes that the farmers settled there around A.D. 40, at the same time when the fort of Valkenburg was built nearby. The settlement was abandoned in the third century. During that entire time, the settlement consisted of two contemporaneously inhabited byre houses. The settlement thus seems to have been small, and the population seems to have remained unchanged.
Apart from the excavated settlements, there are numerous observations, obtained from mapping and stray finds. These are stored in the national database ARCHIS (Roorda & Wiemer 1992; the Archaeological Information System of the Cultural Heritage Agency , RCE). The ARCHIS version, updated to January 2009, has been consulted to obtain an impression of the number of agrarian settlements in the research area from the first and early second centuries. This approach has some drawbacks (see also Vos 2009, 29-30). For instance, most observations are not closely dated, and not every observation represents a rural settlement. Moreover, erosion has caused settlements to disappear in the course of history, and undoubtedly there are also settlements that have not yet been discovered. To estimate the number of rural settlements, observations have only been selected if they comprise multiple finds, if several observations occur within a radius of 200 m, if a cultural layer has been found, and if the observations are located on alluvial ridges, levees and parallel dune ridges. This exercise has yielded 210 possible rural settlements from the Roman period, most of which are located in the river region and the coastal region (fig. 5). The peat region seems to have been sparsely populated.
The question is to what extent the reconstructed number of settlements and the differences in density in the three regions of the research area match the actual situation. It is likely that erosion and sedimentation in the peat region is less or at the most similar to that in the river region. This could lead to the conclusion that the peat region was indeed less densely populated. However, the peat and coastal region have not been mapped in the same intensive and systematic way by field surveys and phosphate mapping. Furthermore, it is likely that the coastal region, where the Roman features may have been covered by the sand of the Young Dunes, harbours more undiscovered settlements than the other two regions.
Figure 5 Reconstructed settlements in the western Lower Rhine limes zone based on ARCHIS database (2009).
It is unlikely that all 210 reconstructed settlements existed at the same time. It is generally assumed that the Early Roman period until circa A.D. 70 was less densely populated, although reality may have been distorted because pottery from that period is not always well recognised (Groot et al. 2009; Heeren 2009; Vos 2009). After the creation of the province of Germania inferior by emperor Domitian, in the 80s A.D., the countryside to the south of the Rhine developed quickly and the number of settlements increased (Groot et al. 2009; Vos 2009; Willems 1986). The settlement pattern to the north of the Rhine has not yet been investigated on such a large scale or with similar detail. As far as we can tell from the data, the number of settlements there does not appear to increase. It rather appears as if settlements were abandoned in the mid-first century (Den Hartog 2009) and that new settlements were founded at other locations in the second/third centuries (Stronkhorst 2004).
The rural settlements in the research area in the first and second centuries A.D. consist of wooden constructions. The discoloured features in the soil are the only remains that are left of these buildings, so that no information is available on the wood use and the origin of the wood. When wood is found, it comes from the lining of wells. It is self-evident that the farmers also obtained their wood from their immediate surroundings in the first and second centuries, just like the military.