This book attempts to understand the commercial and social history of erstwhile Bengal in terms of its links with it neighbouring countries in the northern region of the Bay of Bengal. It touches upon the key issues in both maritime and territorial history such as the early medieval trade revolution and its impact on the borders of Bengal. The discussion focusses on Southeast Bengal - the most economically developed area of Bengal in terms of transport networks, agriculture, artisan products and trade. Most of this area underwent two major transformations in the twentieth century: once as a result of the formation of East Pakistan in 1947 and a second time after the formation of Bangladesh in 1971. The volume concludes with certain major issues of concern between India and Bangladesh at the turn of the twenty-first century.