|This article relies largely or entirely upon a single source. (June 2012)|
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 conclave formalized the tactics that had been adopted by the magistrates of Viterbo against the cardinals in the protracted papal election of 1268–1271, which had produced Gregory X.
Historians have suggested that Gregory X's status as a non-cardinal prior to his election caused him to adopt such a policy that de-emphasized the interests of the College of Cardinals. The goal of Ubi periculum was to limit strategic maneuvering within papal elections to produce faster outcomes, thereby reducing the number of schisms and disputed elections.
The new election rules limited each cardinal to two servants, prevented them from leaving or communicating with the outside world, and restricted the menu progressively on the fourth and ninth days; these rules were frequently bent and sometimes broken entirely in the ensuing conclaves of the next centuries.
Although the first election following Ubi periculum observed its rules and took only one day, its application was suspended and the elections of 1277, 1280–1281, 1287–1288, and 1292–1294 were long and drawn out until Pope Celestine V (another non-cardinal and relative outsider) reinstituted the law of the conclave.
- Latin text 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.