New paleoclimatic data for the Lateglacial clarify climatic phases during the Lateglacial. Cold climate played a key role in limiting Magdalenian expansion from southwest and central Europe This paper presents chronological and geographic data for the different climatic phases to map the expansion of the Magdalenian into northwest Europe. Specifically, it can be seen that initial expansion follows a southwest-northeast trajectory into southern Germany, followed by northern expansion into Belgium, central Germany and the Paris Basin at the end of the Oldest Dryas. During the Bolling and Allerod phases, human occupation intensified in the Paris Basin and contacts and/or territorial exploitation between both the Paris Basin and the Rhineland region with Belgian territory is demonstrated.