The purpose of this paper is to focus on the impact of environmental changes on ancient societies, from the recent Neolithic to the Early Bronze Age (4.2 extreme event). Michel Magny’s recent work has shown that there was a short period of drought in the Mediterranean around 2200 BC (Magny et al 2013). This period might correspond with the establishment of the Mediterranean climate under orbital forcing. In the same time, major switches of Intertropical Convergence Zone are recorded in the speleothem of Dongge cave (China). A series of studies have established that in the South of France, such as the Rhône Valley, an important change occurred in the human settlement system around 2300-2200 BC. In lowland areas the quantity of settlements decreased significantly after a maximal concentration along the river systems during a period of very high hydrosedimentary discharges, dryness and fire activity. It is interesting to note that the exploitation of copper ore resources that had begun in Cabrières (France, Hérault) around 3200 BC, ceased around 2300-2200 BC. In addition, the environmental changes allowed for an exploitation of alpine copper at the same time, as seen in Saint-Véran (France, Hautes-Alpes). Indeed, at very high altitudes, the glacial retreat allowed for an exploitation of copper ore resources available above altitudes of 2400 metres from 2150 to 1650 BC (Les Rousses, Oisan, Isère). Our findings have revealed a growth of human pressure in mountain areas, specifically in the Pyrenees. The exploitation of intermediate areas (piedmont regions –moderately mountainous) in the Basque country took the form of temporary habitations (pastoralism). Others might argue that the data from western France contradicts this pattern : the increase of farms and land parcels number attests to an intensification of the human settlement system. This new kind of management of the landscape and the agro-pastoral areas was undoubtedly under the control of a new elite that emerged around 2200-2100 BC. They buried their dead under large mounds in Armorique or Wessex, and were not out of keeping with third millennium societies, integrating in its symbolic language a reinterpretation of the bell beakers’ set of artefacts, albeit using more luxurious and exotic materials (without any further functional value). The period between 2300 and 2100 BC corresponds to a phase of global environmental threshold in the the south-north atmospheric circulation at the beginning of the Late Holocene due to an orbital forcing. A millenial RCC of 2/3 centuries long (the 4.2 event) is recorded in the same time whose effects are recorded in lakes, fluvial and soils systems of western Europe. The socio-economic modifications introduced may have resulted in a spatial reorganisation at a regional level, but not in a global collapse. , The purpose of this paper is to focus on the impact of environmental changes on ancient societies, from the recent Neolithic to the Early Bronze Age (4.2 extreme event). Michel Magny’s recent work has shown that there was a short period of drought in the Mediterranean around 2200 BC (Magny et al 2013). This period might correspond with the establishment of the Mediterranean climate under orbital forcing. In the same time, major switches of Intertropical Convergence Zone are recorded in the speleothem of Dongge cave (China). A series of studies have established that in the South of France, such as the Rhône Valley, an important change occurred in the human settlement system around 2300-2200 BC. In lowland areas the quantity of settlements decreased significantly after a maximal concentration along the river systems during a period of very high hydrosedimentary discharges, dryness and fire activity. It is interesting to note that the exploitation of copper ore resources that had begun in Cabrières (France, Hérault) around 3200 BC, ceased around 2300-2200 BC. In addition, the environmental changes allowed for an exploitation of alpine copper at the same time, as seen in Saint-Véran (France, Hautes-Alpes). Indeed, at very high altitudes, the glacial retreat allowed for an exploitation of copper ore resources available above altitudes of 2400 metres from 2150 to 1650 BC (Les Rousses, Oisan, Isère). Our findings have revealed a growth of human pressure in mountain areas, specifically in the Pyrenees. The exploitation of intermediate areas (piedmont regions – moderately mountainous) in the Basque country took the form of temporary habitations (pastoralism). Others might argue that the data from western France contradicts this pattern : the increase of farms and land parcels number attests to an intensification of the human settlement system. This new kind of management of the landscape and the agro-pastoral areas was undoubtedly under the control of a new elite that emerged around 2200-2100 BC. They buried their dead under large mounds in Armorique or Wessex, and were not out of keeping with third millennium societies, integrating in its symbolic language a reinterpretation of the bell beakers’ set of artefacts, albeit using more luxurious and exotic materials (without any further functional value). The period between 2300 and 2100 BC corresponds to a phase of global environmental threshold in the the south-north atmospheric circulation at the beginning of the Late Holocene due to an orbital forcing. A millenial RCC of 2/3 centuries long (the 4.2 event) is recorded in the same time whose effects are recorded in lakes, fluvial and soils systems of western Europe. The socio-economic modifications introduced may have resulted in a spatial reorganisation at a regional level, but not in a global collapse.