Inquisition, medieval agency of the Roman Catholic Church to combat heresy, first made official in 1231 when Pope Gregory IX appointed a commission of Dominicans to investigate heresy among the Albigensians of southern France. It aimed to save the heretic's soul, but a refusal to recant was punished by fines, penance, or imprisonment, and often by confiscation of land by the secular authorities. Later the penalty was death by burning. Torture, condemned by the former popes, was permitted in heresy trials by Innocent IV (d. 1254). The accused were not told the name of their accusers but could name their known enemies so that hostile testimony might be discounted. Often the Inquisition was subject to political manipulation. In 1524 it was reconstituted to counter Protestantism in Italy; its modern descendant is the Congregation of the Doctrine of the Faith.
The Spanish Inquisition, founded in 1478 by Ferdinand and Isabella, was a branch of government and was distinct from the papal institution. Its first commission was to investigate Jews and Muslims who had publicly embraced Christianity but secretly held to Judaism or Islam. Under the grand inquisitor Torquemada, it became an agency of official terror—even St. Ignatius Loyola was investigated. It was extended to Portugal and South America and not dissolved until 1820.
In January 1998 the archives of the papal Inquisition, until 1902, were made accessible to researchers.
See also: Torquemada, Tomás de.