Located between Nîmes and Montpellier, the eastern Languedoc has been densely populated since prehistoric times, developing into stable territories structured around proto-urban settlements during the Iron Age. Some are still seen today as villages or towns, while others were deserted for new centres of settlement. The reasons for this evolution are grasped through the spatial dynamic of protohistoric settlement. Following an introduction on the conditions of data gathering and processing in the nearly 300 sites and 250 zones of agrarian spread, we will expose the reasoning and the tools used in order to model the networks of settlement and "finage" (agrarian territories exploited by a rural community). The results underline different phases in the spatial organisation of settlement, allowing us to identify the mutations of protohistoric settlement patterns on several scales. Thanks to ethnological examples, we are able to shed light on the functioning of territorial systems.