The Papal Inquisition Is Established

Firm date

Gregory IX issues statutes against heretics and commissions Dominican friars to seek them out, try them and hand the unrepentant to the secular power. Papal inquisitors begin work at Toulouse; in 1252 Innocent IV orders the cities of northern Italy to force confessions.

The Fourth Lateran Council had made the search for heretics the duty of each bishop, who was to visit suspect parishes and put the neighbours on oath (Fourth Lateran Council, constitution 3).

In 1231 Gregory IX issued statutes of his own. They excommunicate Cathars, Patarenes, the Poor of Lyon and other named groups. Those the church condemns are to be left to the secular court for “the punishment due”. Those who are caught and then return to do penance are to be imprisoned for life; the version in the church’s law book reads, of those who will not return (Gregory IX, Excommunicamus (1231)) (Decretals of Gregory IX X 5.7.15). Supporters lose their legal rights, suspects who do not clear themselves within a year are condemned as heretics, no appeal is heard, and no advocate or notary may act for them. Laymen may not dispute about the faith. Everyone who knows of heretics or secret meetings must report them. Their children to the second generation are barred from church office (Gregory IX, Excommunicamus (1231)).

In November 1231 Gregory wrote to the Dominican prior of Regensburg and a fellow friar. They were to assemble clergy and people and preach, then with chosen helpers “inquire diligently” after heretics and those of ill repute. Any found guilty who would not obey the church absolutely were to be dealt with under the new statutes. Those who abjured were to be absolved and given the customary penance, with care taken against pretended conversions. The letter gives them power to censure anyone who resists and adds that two of them may act if not all can be present (Gregory IX, Ille humani generis (22 November 1231)).

William Pelhisson, a friar of the convent at Toulouse, describes the work there. The pope made two Dominicans inquisitors for the dioceses of Toulouse and Cahors (William Pelhisson, Chronicle pp. 13–14). They offered a time of grace, in which those who confessed fully were promised that they would not be imprisoned, exiled or stripped of their goods (William Pelhisson, Chronicle p. 27). They summoned suspects and heard witnesses. One man, John Textor, protested that he was a married, meat-eating Christian. Pelhisson, who calls him accursed, says that he was condemned in the friars’ cloister, that in the bishop’s prison he then declared himself of one belief with heretics held there, and that he refused to recant and was burned with them. At Cahors the friars condemned dead persons, whose bodies were dragged through the town and burned (William Pelhisson, Chronicle pp. 17–20). In November 1235 the consuls drove the friars out of Toulouse. One of them went to the pope at Rome, and Gregory had the count restore them (William Pelhisson, Chronicle pp. 37–41).

In 1252 Innocent IV ordered the city governments of northern Italy to hand arrested heretics to the bishop or the inquisitors within fifteen days, to apply the laws against heretics to those condemned, and to force those arrested, stopping short of loss of limb or danger of death, to confess their errors and name others, as thieves are forced to name accomplices (Innocent IV, Ad extirpanda 24–26).

How this is dated

Firm date. Fixed by contemporary documentation and not seriously disputed.

The statutes beginning Excommunicamus are assigned to 1231 by their editor (Gregory IX, Excommunicamus (1231)). The letter to the Dominicans of Regensburg, dated at Rieti on 22 November in Gregory’s fifth year, 1231, calls them his statutes against heretics “lately published” (Gregory IX, Ille humani generis (22 November 1231)). The year is that of the statutes and of this commission to friars; the inquisitors in Languedoc whom Pelhisson describes were at work by 1235, the year he gives for the expulsion of the friars from Toulouse (William Pelhisson, Chronicle pp. 37–41).

Primary sources

Constitutions of the Fourth Lateran Council

The Fourth Lateran Council · November 1215 · Latin

Decretals of Gregory IX (Liber Extra)

Compiled by Raymond of Penyafort for Gregory IX · 1234 · Latin

Ad extirpanda

Innocent IV · 15 May 1252 · Latin

Every citation on this page was independently checked against its source on 3 October 2026.

In context

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  1. November 1215, firm date
  2. about 1173, estimated date
  3. 22 December 1216, firm date
  4. 1209 to 1229, firm date

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  1. 30 May 1431, firm date
  2. 1478 to 1492, firm date

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