Living along the Limes: Landscape and settlement in the Lower Rhine Delta during Roman and Early Medieval times

Abstract

River environments have played a vital role in human history. However, the intensive exploitation of rivers and deltas has increasingly caused problems, particularly in lowland deltas. Solving the current problems also requires a more fundamental understanding of how natural and societal systems interact. How did the early societies responded or adapted to, or prevented changes and dynamics, of these wetland areas? Answering this question would be a first and important step in the further understanding of the interaction between social and natural systems in deltas. The wealth of geological and archaeological data in the Netherlands, the publicly-available databases, and excellent preservation conditions constitute a perfect case to provide detailed palaeogeographical reconstructions of a complete distributary, the Oude Rijn, and to decipher the effect of the landscape and its dynamics on settlement locations in the delta in various time periods on a larger scale. From the AD 40s onwards a dense Roman military system was established along the Oude Rijn in the Netherlands. Long since, it has been questioned why this system was established in a wetland area and even was turned into the northwest frontier of the Roman Empire, the Limes. Therefore, a new and highly-detailed palaeogeographical map was constructed. From this map we conclude that this military system (a combination of forts and watchtowers) was established to watch over the river Rhine and its traffic, and to guard all waterways that gave access to the river Rhine from the Germanic residential areas further north and from/ to the Meuse tributary further south in the delta. Until recently, it was assumed that the Roman army in the Rhine-Meuse delta was mainly supplied with products transported over medium and long distances. A review of the archaeological data leads us to the argument that the Roman army procured wood and food (especially cereals and beef) from agrarian settlements in the immediate surroundings. We also modelled and quantified the carrying capacity of the landscape and the demand and supply of the Roman army along the Oude Rijn regarding wood and food for the period AD 40-140. Our calculations reveals that the carrying capacity of the landscape was larger than hitherto assumed, and that the local population was probably much more involved in the provisioning of the Roman army than previously assumed. Furthermore, the formation and landscape development of crevasse splays was analysed to increase the understanding of the attractiveness of these often short-lived landscape features for settlement and human use in general. Recent archaeological research has shown that these landscape features unexpectedly have provided favourable sites for settlements already from Neolithic period onwards. LIDAR data combined with digital coring databases and/or detailed soil maps have proven to be an excellent method for the identification and mapping of crevasse splays and the archaeological sites these contain. In addition, integrated geological and archaeological datasets to demonstrate the concurrence of the gradual abandonment of the Oude Rijn and Kromme Rijn - the main Rhine branch that hosted the Roman Limes -, the development of human habitation in the area, and the interactions between them. A continued geomorphic development during this period, which includes the ‘Dark Ages’ (AD 450-1000), appears to have been crucial in the development of Utrecht from a Roman army fort to a Medieval ecclesial centre. This thesis shows that Detailed landscape reconstructions are crucial for interpreting past changes in settlement development and land use in dynamic landscapes such as lowland delta areas.