Five specific Iberian factors made the medical-murder myth unusually durable.

Evidence

The exceptional ‘success’ of the myth of medical murder targeting Jews and their converted descendants—if this ‘success’ can be measured by its repetition in printed works and longevity across the centuries—is in no small part due to factors that were particular to the situation of Jews/judeoconversos in the early modern Iberian world. The reasons why the judeoconversos were targeted by such a medical conspiracy theory are certainly numerous: (1) the success of Jewish medical practitioners in the Iberian Christian kingdoms during the medieval period; (2) the existence of a medieval myth of Jewish medical murder and the Catholic Church’s support for laws that (unsuccessfully) sought to prevent Christians from interacting with Jewish doctors; (3) the fears generated by the invisibility of alleged judaisers who were no longer forced to wear distinguishing clothing; (4) the appearance of the forged letters between the judeoconversos of Toledo and Jews of Constantinople; and (5) the credibility conferred on the conspiracy theory by the officially sanctioned statutes of racial purity, introduced by numerous medical faculties and schools. — James Renton, Ben Gidley (eds.), Antisemitism and Islamophobia in Europe, 421

Categorization

• XREF: Connects to the reader’s interest in how conspiracy theories need local credibility conditions; the list of factors echoes Milgrom’s institution-origins framing (conditions for a belief system’s viability).
• QUESTION: Why did the same conversion crisis not produce an equivalent morisco medical-murder myth despite similar dynamics? Worth chasing as a comparative case.