Summary of the thesis For more than 11,000 years ago, human groups entered and utilized territories that today belong to Norway. The colonization process took place after the last Ice Age, within a period of 1500 years that was characterized by great environmental changes: The climate shifted from arctic to sub-arctic/maritime, the terrestrial ice sheet melted and the sea-ice withdrew, cold tolerant vegetation and fauna were partly replaced by new species as the temperatures increased. This thesis is a study of how humans dealt with the climatic oscillations and adapted to a landscape that was spatially diverse and in constant change. The dissertation particularly focusses on humans’ relations to the coastal zone and productive marine habitats with Central Norway as key area – a region that holds several hundred settlements from the earliest settlement phase. On the basis of archaeological sites and artifact assemblages from the first phase of the Early Stone Age (9500–8000 BC), spatial and temporal variations in settlement patterns and artifact inventories are analyzed and discussed according to the contemporary environmental circumstances: Do we find different cultural expressions in different geographic and topographic zones? Do we find changes in adaptive strategies through time? The results suggest that differences in the resource base had little impact on tool inventories and settlement layout. Site location does to a larger degree appear to be structured by climatic variations. The key to a successful approach to the Norwegian landscape probably lay in the combination between well-functioning, versatile technological systems and a flexible mobility pattern. The thesis finally deals with behaviour and adaptation as global phenomena through a comparative study of archaeological records from Tierra del Fuego in Argentina. The regions are climatically and topographically comparable, but geographically and culturally detached, making them suitable for an examination of how the physical surroundings affected the choice of mobility strategies. The two cultures appear to have very similar strategies, which supports the notion that there are some universal principles behind the relations between humans and environment.