papal election, election of the pope by the college of cardinals meeting in secret conclave in the Sistine Chapel not less than 15 nor more than 18 days after the death of the previous pontiff. In the case of a resignation, the conclave may begin earlier. The election is by secret ballot; Pius XII fixed the electoral majority at two thirds plus one vote. The election itself confers on the new pope full jurisdiction; no further formality is necessary. The elected pope may decline; if so, the balloting resumes.

The secrecy of the conclave is assured by shutting off the cardinals completely from the outside world, but the results of a voting session are revealed to the outside by the burning of the paper ballots. If the vote is inconclusive, substances are added to produce black smoke; white smoke, which is followed by the tolling of St. Peter's bells, signifies that a new pope has been chosen. At one time expedition was encouraged by severe restriction of the cardinals' diet after a few days.

Theoretically any adult male Roman Catholic is eligible to be pope, but long-standing practice limits the candidates to cardinals. Before John Paul II was elected in 1978, the last non-Italian elected was Adrian VI, a Netherlander, in 1522. Francis I, elected in 2013, was the first person from the Americas to be elected pope. In the vacancy of the Holy See the entire college of cardinals holds the papal jurisdiction, but its powers are extremely limited.

The popes were at first elected like other bishops, by the clergy and laity of the diocese; serious political interference was discouraged in 769 by the exclusion of the laity from papal election. Participation in the election was limited (1059) to the cardinals by Nicholas II; the conclave was set up (1274) in its modern form by Gregory X. Decrees by Pius XII in 1945, John XXIII in 1962, Paul VI in 1975, John Paul II in 1996, and Benedict XVI in 2013 now fix the regulations for papal elections.