The medieval popes have been the targets of many attacks in recent times, and perhaps on no single point have they been subjected to such vilification as on that of the ""tradition of anti-Semitism"" which they are supposed to have introduced into the Church. It is certainly true that persecution and slaughter of the Jews occurred with almost mechanical regularity during the medieval period; it is true that, between pogroms, they were herded into ghettos, excluded from most respectable professions, and generally never allowed to forget that they were ""killers of Christ"" and ""a perfidious people."" It is arguable, too, that the medieval papacy, eager as it was to assume the government of Europe , was theoretically responsible for the behaviour of Christendom at large. The purpose of this book, precisely, is to examine all those acts of anti-Semitism and to see from whence they came -- were they the practical effects of an official polic of the Holy See, or were they in fact due to the peculiar beliefs, monetary predicaments, or glandular secretions of individual Christians qua individuals? The author's method has been, first, to examine relevant medieval documents, and then to comment on the import and significance of what those documents record. Mr. Synan has no axe to grind, no pet theory to set forth, no favorite pope to exonerate; he allows his material to speak for itself. He has produced that rare avis, a literate, but thoroughly scientific and painstakingly documented, historical study. It is a book which is as entertaining as it is instructive, and should be indi to any student of ecclesiastical, medieval, or Jewish history , and indeed to any general reader with a taste for the history of ideas.