This thesis presents the results of an investigation into the Clactonian assemblages of Middle Pleistocene souther Britain. By exploring other non-biface assemblages (NBAs) reported from elsewhere in Europe it seeks to illuminate our understanding of the British assemblages by viewing them in a wider context. It sets out how the historical and geopolitical context of Palaeolithic research has influenced what is investigated and how, as well as interpretations of assemblages without handaxes. A comparative study of the assemblages themselves based upon primary data gathered specifically for that purpose concludes that while there are a number of non-biface assemblages elsewhere in Europe the Clactonian assemblages do appear to be a phenomenon unique to the Thames Valley in early MIS 11. However, traditional explanations for this phenomenon, such as cultural variation, cultural migration and pioneer populations are challenged and a new interpretation centred on the concept of a default flaking pattern is proposed