Summed probability distributions of radiocarbon dates are used to make inferences about the history of population fluctuations from the Mesolithic to the late Neolithic for three countries in central and northern Europe: Germany, Poland and Denmark. Two different methods of summing the dates produce very similar overall patterns. The validity of the aggregate patterns is supported by a number of regional studies based on other lines of evidence. The dramatic rise in population associated with the arrival of farming in these areas that is visible in the date distributions is not surprising. Much more unexpected are the fluctuations during the course of the Neolithic, and especially the indications of a drop in population at the end of the LBK early Neolithic that lasted for nearly a millennium. Possible reasons for the pattern are discussed.