Papal conclave, 1830–31

Coat of arms during the vacancy of the Holy See
Dates and location
14 December 1830 – 2 February 1831 Quirinal Palace, Papal States
Key officials
Dean	Bartolomeo Pacca
Sub-Dean	Pietro Francesco Galleffi
Camerlengo	Pietro Francesco Galleffi
Protopriest	Luigi Ruffo-Scilla
Protodeacon	Giuseppe Albani
Election
Vetoed	Giacomo Giustiniani
Ballots	83
Elected Pope
Bartolomeo Alberto Cappellari Name taken: Gregory XVI
← 1829 1846 →

A Papal conclave was held commencing 14 December 1830 after the death of Pope Pius VIII. It did not conclude until the 2 February 1831 election of Mauro Alberto Cappellari as Pope Gregory XVI.

Initially the chief candidates included Emmanuele De Gregorio and Bartolomeo Pacca, who had been papabili in the 1829 conclave, plus Giacomo Giustiniani, who was a long-serving papal diplomat but was vetoed by King Ferdinand VII.

However, it became clear eventually that none of them could gain the support of two-thirds of the cardinals, and with Prince Klemens Wenzel von Metternich wanting a very strong Pope to hold firm against the flood of revolution haunting Europe at the time of the conclave, Giuseppe Albani intervened. He proposed Vincenzo Macchi as his candidate, but few of the other cardinals saw Macchi as suitable for the papacy. Cappellari appeared as an alternative to both De Gregorio and Macchi only when the conclave was well-advanced, but even though Albani worked against him, Cappellari eventually took the lead and won the election.

No conclave since has lasted as long as a week, but at the time no conclave since 1667 had lasted less than three weeks. The conclave took eighty-three ballots to deliver a two-thirds majority to a candidate, whereas no conclave since has taken more than fourteen.

Some 45 of the 54 living cardinals participated, and Bartolomeo Pacca presided as Dean of the Sacred College. Cappellari, then a Camaldolese priest and prefect of the Congregatio de Propaganda Fide, was also the last Pope not a bishop when elected.