1220: Dominican order founded.

1231: Pope Gregory IX authorizes Dominicans to examine Cathar and other Christian heretics in southern France and Italy, the so-called "medieval inquisitions."

1357: Nicolas Eymeric compiles his manual of instruction for inquisitors, the Directorium Inquisitorum.

1391: Massacres of Jews across Spain; thousands forced to convert to Christianity.

1460s: Alfonso de Espina writes The Fortress of the Faith against Jews, Muslims and other Enemies of the Christian Faith.

1478: Pope Sixtus IV authorizes the Spanish Inquisition at the request of Ferdinand and Isabella, the "Catholic Monarchs" of Spain. (1:3, 2:1-2)

1480: First Spanish Inquisition tribunal becomes active in Seville; targets converts from Judaism (conversos) suspected of remaining loyal to their ancestral religion.

1483: Tomás de Torquemada named first Inquisitor-General of the Spanish Inquisition; organized inquisitorial tribunals in Jaén, Córdoba and Ciudad Real.

1492: Jews expelled from Spain; last Muslim enclaves in Spain seized.

1496: Jews expelled from Portugal; those remaining forced to convert according to edict which followed.

1515: Pope Leo X institutes pre-press censorship; not enforced.

1517: Martin Luther nails his "Ninety-Five Theses" on the door of Castle Church in Wittenberg; Reformation begins.

1536: Calvin publishes the first edition of his Institutes of the Christian Religion.

1540: First auto-da-fé conducted by the Portuguese Inquisition; Jesuit order founded.

1542: Bernardino Ochino, head of Franciscan Capuchin order, flees Italy, converts to Protestantism. Pope Paul III establishes the Roman Inquisition. Limited press censorship, banning of Ochino’s works.

1545: Opening session of the Council of Trent.

1553: Michael Servetus burned alive by Calvinist authorities in Geneva after fleeing persecution in Spain.

1559: Pope Paul IV’s Pauline Index. Trials of prominent Spanish Protestants in Valladolid and Seville; focus of Spanish Inquisition temporarily shifts to Protestantism.

1563: Last session of the Council of Trent.

1564: Tridentine Index published.

1570: Spanish Inquisition establishes tribunals in Mexico and Peru.

1571: Congregation of the Index established by Pope Pius V.

1588: Pope Sixtus V creates Congregation of the Holy Roman and Universal Inquisition.

1600s: Royal pressure to allow Jews to return to Portugal; Inquisition responds with increased anti-semitic and anti-converso persecutions. (see autos-da-fé)

1633: Trial of Galileo Galilei by Roman Inquisition.

1720s: Wave of anti-converso trials worldwide. (see autos-da-fé)

1807: Napoleon defeats Spain, Spanish Inquisition halted.

1815: Spanish Inquisition restored by Ferdinand VII; continued debates over its existence.

1834: Spanish Inquisition officially ended.

1843: Edgar Allen Poe publishes The Pit and the Pendulum.

1908: Roman Inquisition becomes Holy Office.

1965: Pope Paul VI reorganizes Holy Office, renames it Congregation of the Doctrine of the Faith.

1966: Index of Forbidden Books abolished.