This work investigates the complex financial and political relationship between Jewish bankers and the Roman Catholic Church from the thirteenth to the seventeenth century. Leon Poliakov, a noted historian of antisemitism and European history, utilizes archival records and historical documentation to analyze how the Papacy navigated its reliance on Jewish capital despite prevailing theological prohibitions against usury. The text argues that this economic interdependence created a precarious environment for Jewish communities, oscillating between periods of protection and systemic persecution based on the fiscal needs of the Holy See.

Historians recognize this text as a foundational study on the intersection of medieval finance and ecclesiastical policy. Scholars frequently cite Poliakov's work for its meticulous archival research and its objective analysis of the economic realities that dictated papal-Jewish relations.