Ubi periculum (Latin: Where danger) was a papal bull promulgated by Pope Gregory X during the Second Council of Lyon on 7 July 1274 that established the papal conclave as the method of selection for a pope. The regulations for a conclave drew on the experiences of the Cardinals, who had been subjected to the tactics adopted by the magistrates of Viterbo against the cardinals in the protracted papal election of 1268–1271, which had produced Gregory X.
A pair of political scientists has suggested that the fact that Gregory X was not a cardinal before his election to the Papacy caused him to adopt a policy that de-emphasized the interests of the College of Cardinals. Such an interpretation is unlikely, or at least incomplete. The goal of Ubi periculum was to limit dilatory tactics and distractions within papal elections, and outside intrusions which might impinge upon the freedom of the electors; it was certainly intended to produce faster outcomes, and, by making the rules more explicit and detailed, to reduce the chances of schism and disputed elections. The imposition of monastic-style modes of living inside the Conclave may also have been intended to lift the minds of the electors out of the everyday business of governing the church, and focus their attention on the spiritual importance of their activity.
Ubi periculum appears to have drawn from the election procedures of the Dominican constitution of 1228 as well as the communes of Venice (1229) and Piacenza (1233). This should not cause surprise, since Gregory X's closest collaborator, Cardinal Peter of Tarantaise, Bishop of Ostia, was a Dominican. Cardinal Bonaventura, Bishop of Albano (who died in 1274) was a Franciscan. And Cardinal Bertrand de Saint Martin, Bishop of Sabina (appointed in 1273) was a Benedictine.
Gregory X's Constitution with respect to conclaves legislated a number of important points:
- that a meeting for the election of a pope should be held at a suitable place, where the Pope and his Curia were residing when the Pope died; if they were at a villa, or a country village, or a town, they should proceed to the nearest city in the diocese (unless it was under an interdict).
- that a meeting for the election of a pope should not take place until the space of at least ten days had intervened;
- that all cardinals who were absent from the Conclave should have no right to cast a vote;
- that not only absent cardinals, but also men of every order and condition, are eligible to be created the Roman pontiff;
- that, at the conclusion of the Novendiales, and the Mass of the Holy Spirit sung on the tenth day, all the cardinals who are present should be enclosed in the palace where the Pope died; along with two or, if they are ill, three or four servants; none may enter or leave, except on account of illness. There should be no interior walls, but each cardinal's quarters should be separated from the rest by cloth drapes, and they should live in common.
- that the place of the conclave and its entries should be carefully guarded;
- that the Cardinals may not leave the Conclave for any reason, until a new pope has been elected;
- that Cardinals who arrive after the enclosing of the Conclave, and before the election of a new pope, have the power to enter the Conclave and vote along with the others, and no Cardinal can be excluded for any reason, not even if he be excommunicated;
- that, if a pope has not been elected in three days, then cardinals are permitted to have only one dish at their meals;
- that, in holding the deliberations, no one is to be put under an anathema, no one is to engage in bribery, or to make any promises, or by going around politicking to promise a cardinal anything once he has been created pope. During the Conclave, the cardinals are to engage in no other business than completing the election;
- that no one can be elected pope with out the votes of two-thirds of the Cardinals present in the Conclave;
- that, upon the death of a pope, all magistracies and offices cease and vacate their functions, except for the Major Penitentiary and the Minor Penitentiaries, and the Chamberlain of the Holy Roman Church (Camerlengo).
The first election following Ubi periculum observed its rules and took only one day, 20-21 January, 1276. The application of "Ubi periculum", however, was suspended by Pope Adrian V, in consultation with the cardinals, since, on the basis of the Conclave of January, 1276, he wished to make adjustments and improvements in the regulations. But Adrian V died only thirty-nine days after his election, and had no opportunity to carry out his revisions. The elections of 1277, 1280–1281, 1287–1288, and 1292–1294 were long and drawn out, though the suspension of "Ubi periculum" was only one contributing factor. The interference in papal elections by the Kings of Sicily, Charles I and Charles II, and the struggles between a French faction of Cardinals and an Imperial faction, complicated and delayed the selection of a new pope. Pope Celestine V (another non-cardinal and Benedictine monk) reinstituted the law of the conclave.
- Latin text of Ubi periculum. Joannes Dominicus Mansi, Sacrorum conciliorum nova et amplissima collectio, editio novissima, Tomus 24 (Venice 1780), 81-86. English translation of "Ubi periculum"
- Josep M. Colomer and Iain McLean. (1998). "Electing Popes: Approval Balloting and Qualified-Majority Rule". The Journal of Interdisciplinary History, Vol. 29, No. 1, pp. 1-22.
- William Cartwright, On Papal Conclaves (Edinburgh 1868), 9-29.
- These are summarized from the Constitution 'ubi primus', by Franciscus Pagi, Breviarium historico-chronologico-criticum illustriora pontificum Romanorum, Conciliorum Generaliorum acta... III (Antwerp 1718), pp. 406-408.
- Sede Vacante and Conclave of January, 1276 (Dr. J.P. Adams).
- Sede Vacante and Conclave of June-July, 1276 (Dr. J.P. Adams).
- Fritz Walter, Die Politik der Kurie unter Gregor X (Berlin 1894), 8-32. Joseph Maubach, Die Kardinale und ihre Politik um die Mitte des XIII. Jahrhunderts (Bonn 1902). F. Gregorovius, History of Rome in the Middle Ages, Volume V.2 second edition, revised (London: George Bell, 1906) 455-477. H. D. Sedgwick, Italy in the Thirteenth Century Volume II (Boston-New York 1912) 71-80.
- Pope Celestine legislated in the constitution Quia in futurorum (issued from Aquila, 28 October 1295), and another on 10 December, 1294, to the same effect: A. Theiner (ed.), Caesaris S.R.E. Cardinalis Baronii Annales Ecclesiastici Tomus 23, under the year 1295, §17, p. 143 and p. 144.