Jews in the Mediterranean Diaspora was the first book to provide a comprehensive survey of the history of the Jews in the Mediterranean Diaspora in the Hellenistic and early Roman period. Uniquely, it combines a study of all the important Jewish communities with a thorough examination of the Diaspora literature as a whole.

Most studies of Jews in the period from Alexander to Trajan have concentrated almost exclusively on Jerusalem and Judea. John Barclay assembles and analyzes evidence about the Jewish communities in Egypt, Syria, Cyrenaica, Rome, and Asia. Barclay's ambitious goal is to describe, as precisely as the evidence allows, the varying levels of assimilation and antagonism between Jews and the non-Jewish communities in these areas for this 440-year period. For this new edition Barclay has written a new introduction to take account of the changes in the academic debate since the work was first published. This remains a crucial reference for all scholars and students with an interest in Second Temple Judaism, Hellenistic Judaism and early Christianity.