Marranos in the context of "Crypto-Jews"

The Massacre of 1391, also known as the pogroms of 1391, refers to a murderous wave of mass violence committed against the Jews of Spain by the Catholic populace in the crowns of Castile and Aragon in 1391. It was one of the most lethal outbreaks of violence against Jews in medieval Spain, and in medieval European history. Anti-Jewish violence then continued throughout the "Reconquista", culminating in the 1492 expulsion of the Jews from Spain. The first wave in 1391 marked the extreme of such violence.

Under duress, Jews began to convert en masse to Roman Catholicism across the Iberian Peninsula after the massacre, resulting in a substantial population of conversos known as Marranos. Catholics then began to accuse the conversos of secretly maintaining Jewish practices, and of thus undermining the newly united kingdom's nascent national identity. In 1492, the Catholic Monarchs of Spain Ferdinand and Isabella issued the Alhambra Decree, which ordered the expulsion of Jews who had not converted to Catholicism. The resulting diaspora came to be known as the Sephardic Jews.

An inquisition was a Catholic judicial procedure in which ecclesiastical judges could initiate, investigate and try cases in their jurisdiction. Popularly the Inquisition became the name for various medieval and reformation-era state-organized tribunals whose aim was to combat heresy, apostasy, blasphemy, witchcraft, and customs considered to be deviant, using this judicial procedure. Violence, isolation, certain torture or the threat of its application, have been used by inquisitions to extract confessions and denunciations. Inquisitions with the aim of combatting religious sedition (e.g. apostasy or heresy) had their start in the 12th-century Kingdom of France, particularly among the Cathars and the Waldensians. The inquisitorial courts from this time until the mid-15th century are together known as the Medieval Inquisition. Other banned groups investigated by medieval inquisitions, which primarily took place in France and Italy, include the Spiritual Franciscans, the Hussites, and the Beguines. Beginning in the 1250s, inquisitors were generally chosen from members of the Dominican Order, replacing the earlier practice of using local clergy as judges.

Inquisitions also expanded to other European countries, resulting in the Spanish Inquisition and the Portuguese Inquisition. The Spanish and Portuguese inquisitions often focused on the New Christians or Conversos (former Jews who converted to Christianity to avoid antisemitic regulations and persecution), the Marranos (people who were forced to abandon Judaism against their will by violence and threats of expulsion), and on the Moriscos (Muslims who had been forced to convert to Catholicism), as a result of suspicions that they had secretly maintained or reverted to their previous religions, as well as the fear of possible rebellions, as had occurred in previous times (such as the First and Second Morisco Rebellions). Spain and Portugal also operated inquisitorial courts not only in Europe, but also throughout their empires: the Goa Inquisition, the Peruvian Inquisition, and the Mexican Inquisition, among others. Inquisitions conducted in the Papal States were known as the Roman Inquisition.