The Impact of the Mid-Holocene Climate Changes on the Genesis and Development of the Early Settlements in the North of Central Iran

In the Holocene, there has been a sudden and severe climate change that has affected the process of cultural evolution, subsistence system, demographic change, and the pattern of the distribution of human settlements. Palaeoclimatological studies show that in the second half of the 7th millennium BC, during a cold and dry climatic event, with a peak of about 6200 BC, the settlement conditions, in particular in some parts of the Northern hemisphere, were significantly disturbed. After this period, the air temperature rose sharply and replaced the warm and dry climate from the beginning of the 6th millennium BC. From the second quarter of the 6th millennium BC, gradually, the amount of humidity increased and the air temperature decreased, so that from the beginning of the second half of the 6th millennium BC, more favorable climate conditions were created for agricultural activities. The early evidence of the human settlements in the North of Central Iran region mainly belongs to the beginning of the sixth millennium BC. Due to the lack of architectural evidence from the first half of the 6th millennium BC in this region, human societies were probably semi-sedentary. From about 5400 BC, sedentary-farmer settlements with architecture were established and gradually their number increased. In the early 5th millennium BC, a warm and dry climatic change caused the interregnum/collapse of the settlements in the region. Therefore, the time of the genesis and prosperity of the early settlements in the North of Central Iran was related to the climatic conditions and occurred in an appropriate climate period between two dry periods.