Michael Toch’s contribution, ‘Jewish Demographics and Economics at the Onset of the European Middle Ages’, deals with the knotty question of the origin of European Jewry. Toch contests the controversial claim that both Ashkenazi and Sephardi communities were descendants of converts (notably the Khazars). He emphasizes the continuity of Jewish presence within the Eastern Roman (Byzantine) Empire, which eventually resulted in immigration northward into the European continent. Toch concludes that these later European Jewish communities, who emerged with a fully-formed culture in a short period of time, were rabbinic from the outset.