This paper presents a work in progress within the project « Modeling the role of socio-environmental interactions on Ancient Settlement Dynamics - ModelAnSet » (UCAJEDI Academy 2 « Complex Systems ») developed by archaeologists, historians, palaeoenvironmentalists and computer scientists at University Côte d’Azur (Nice). Agent-Based Modeling is used to explore the respective role of environmental and social factors in the evolution of the settlement pattern and dynamics during the Roman period in South-Eastern France. The model aims at simulating the impact of the climatic and macro-economical conditions on the behavior of Gallo-Roman landowners. According to the profit (both economical and symbolic) they derive from their rural exploitations, wich depends both on natural (soil fertility and changing climatic conditions) and socio-economical factors (social status and economical power of the landowner, macro-economical context), the landowners can decide to maintain without change, improve, enlarge or abandon their exploitations or to create a new one. The data (archaeological, epigraphical and palaeoenvironmental) collected and studied over more than 10 years in the territory of the Roman colony of Fréjus (Var, France) is used to define the model parameters and behavioral attributes of the cognitive agents. The paper will present the conceptual model and a first implemented version of the ABM.