This theory has been extensively studied on a national level, but few local case studies trace the transition from the multiethnic organized crime of the 1930's and 1940's to the (supposed) Italian hegemony of the years since 1960. Philadelphia provides an excellent opportunity for such a study, as the base of a strong Jewish-dominated structure before 1960 and a 'Mafia town' thereafter. A major concern of this article is the manner in which the history of crime in the city was retroactively rewritten during the 1970's, in order to provide a basis for contemporary theories and bureaucratic needs. (Author abstract)