Religious issues aside, there was another issue which made Jews vulnerable in the late 14th and 15th centuries. As in the rest of Medieval Christian Europe, Jews in the Iberian Kingdoms were designated as the property of the Crown. They benefited the Crown economically providing unique sources of revenue to them. Their residence was allowed and tolerated due to the benefits it provided the Crown and the unique roles Jews often served economically. As David Nirenberg explains:
“This special relationship between Jews and rulers proved tremendously useful to European monarchs and magnates trying to establish and expand their power in the eleventh, twelfth, and thirteenth centuries. The most notorious way in which control of the Jews served to extend sovereign power was through money lending.
Any number of European princes channeled Jewish economic activity toward lending at interest to Christians, so that they could then expropriate a considerable share of the proceeds from the Jews in the form of loans, taxes, and extraordinary seizures called captiones, ‘takings.’”
The position of the Jewish community with respect to its financial vassalage to the Crowns of Castile and Aragon is clear. The economic responsibilities of the community towards the Crown were substantial as were the involvement of certain Jews in money lending to Christian debtors. The position of Jews in Castile in relation to the Christian population was particularly exacerbated by the practice of usury which was needed by the latter, but made Jews vulnerable in difficult economic times.
There, Jewish participation in money lending was coupled with a prominence of Jewish royal bureaucrats and courtiers often skilled linguistically. This unique situation would prove extremely problematic. The fact that Jews generally supported a strong, centralized monarchy which could protect them, added to the resentment that nobles as well as peasants felt towards them.
When religious sentiment was added to the mix, the results would prove explosive. The same would prove true for Conversos who viewed a strong monarchy as the most viable option for securing their safety and often assumed the roles which Jews had largely occupied previously. In addition to the charge of continued allegiance to Judaism, the placement of Conversos in such positions only added to the view that they remained connected to their Jewish past.
 David Nirenberg, Anti-Judaism: The Western Tradition, (W.W. Norton & Company: New York, 2013), 194.
 In Aragon, Jews had been officially prohibited from serving in royal positions since 1283.Natalie Oeltjen, “Crisis and Regeneration: The Conversos of Majorca, 1391 – 1416.” (PhD diss., University of Toronto, 2012), https://tspace.library.utoronto.ca/bitstream/1807/32784/3/Oeltjen_Natalie_B_201206_PhD_thesis.pdf. .4.
 Yitzhak Baer, A History of the Jews in Christian Spain Volume 2, (Philadelphia: Jewish Publication Society, 1961), 306.
By Rabbi Juan Bejarano-Gutierrez, the director of the B’nei Anusim Center for Education, and author of What is Kosher?