'Purity of Blood' and The Spanish Inquisition (1492)

The Inquisition, intended to root out Catholic heresies and heretics, was created through a papal bull at the end of the 12th century. Although the Inquisition of Spain is most well known, the bull was intended to track down and put an end to heresy throughout all the lands of Christendom.
The Jews of Europe were under constant pressure to convert, were forced to wear identifying clothing, to sit in church as observers of Catholic services. Since conversion was typically coerced, sometimes at the point of a sword, the converts were always suspected of insincerity. Those “Jews” most likely to be targeted by the Inquisition were the Conversos, suspected of secretly remaining Jews, of practicing the religion secretly at home while passing as Catholic in the street. But this was not always the case. The head of Poland’s Inquisition, St. John Capistrano, also known as the “Scourge of the Jews,” targeted both Jews and converts (See, Grosser, Paul and Halperin, Edwin, 1978, Antisemitism: Causes and Effects, p. 136).
In addition to its mission to track down heresy, the Spanish Inquisition was also used to unify Spain and consolidate Catholic power under the monarchs Ferdinand and Isabella. Its primary target was the expulsion of the Moors from Spain. The Jews, that other foreign population, were given the choice of expulsion or conversion.
 
 
In the early years the Inquisition was most concerned with establishing the credibility of those conversions. As the years went by and some Conversos rose to positions of authority within the church bureaucracy, including, according to some sources, the head of the Inquisition, Tomas de Torquemada. Fear of “Jewish influence” increased as more Jews converted, which attracted the attention of the inquisitors. The Conversos were tortured to extract a confession, and then burned at the stake for “confessing.”
Estimates vary regarding the actual number of Conversos who died in the fires of the Inquisition. Based on statistics drawn from the records of Autos da fe, as many as 8,000 may have been burned at the stake. Jewish Virtual Library estimates that, in addition to “Conversos” directly murdered by the Spanish Inquisition, “[t]ens of thousands of refugees [expelled from Spain by the 1492 edict] died while trying to reach safety.”
In response to fear of the “Jewish Influence” posed by the Conversos, the Inquisition took a step beyond determining the degree of sincerity of the new Catholics by extending their investigation into Catholic pedigree back generations. Purity of blood, or limpieza de sangre, became the hallmark of who was, and not, a Catholic.
“Now Jewishness is… a permanent inborn characteristic that even baptism does not remove,” (Nicholls, William, 1993, Christian Antisemitism, A History of Hate, p. xxi). “Those who wished to hold public office had to present a certificate … showing that there were no Jews in their lineage, that they were free of… mala sangre, bad blood (ibid. pp. xx-xxi).
  
Most recent in this series, Antisemitism and Jewish Survival:
1. From Black Death to Blood Libels: The Jews did it!
2. The Crusades (1096-1272): ''Rehearsal'' for Holocaust
3. Anti-Jewish Persecution and the failed Parousia: the year 1000