Western European LGM humans confined to glacial refugia by climate and ecology. Agent-based model simulates mobility and survival based on habitat suitability. Large refugium spans southern France and northeastern Spain. Higher population growth in central refugium causes continuous out-migration. Out-migration homogenizes genetics across Western Europe. Italian peninsula shows possible genetic exception. Results match archaeological material culture data. Model tracks regionally specific genetic markers over time. Predicts patterns for future ancient DNA studies. Habitat suitability minimally affects death rates. Population size grows with higher habitat benefit. Foraging radius influences regional occupation. Larger refugia form under high habitat benefit and mobility. Genetic structure weakens with out-migration from central refugium. Metapopulation starts at 7000 agents. Simulations use ethnographic and archaeological data.