Volume have been written on India's contacts with other countries during the historical period but there is hardly a work which deals exclusively with such contacts during the prehistoric and protohistoric periods, i.e., from the Palaeolithic period to the Mauryan Period. There are, however, a number of archaeological reports of excavations conducted in India and outside which contain a good deal of information on material culture throwing significant light on the subject, but it has not been pieced together earlier to work out a connected history of the entire period under consideration. Similarly, there is a good deal of literary and traditional evidence which needed a fresh treatment in the light of new historical discoveries and reassessment of the old data. In the present monograph an attempt has been made not only to organize this information into the historical perspective of time and space but also to present a reappraisal of a number of theories built by different scholars working in the field.