The conclave is the tradition of electing the Pope in the Catholic Church, rooted in a long history and internal crises within the Church. The modern conclave system began to take shape in the 13th century, particularly after the death of Pope Clement IV in 1268. At that time, the papal election dragged on for nearly three years in the city of Viterbo, Italy, prompting local citizens to lock the cardinals in and restrict their food supply to hasten a decision. This event led Pope Gregory X to issue the official decree “Ubi Periculum” in 1274, establishing the conclave as a mandatory and secretive method for electing a new Pope.
The conclave process begins 15 to 20 days after the Pope’s death, allowing time for mourning and for cardinals from around the world to gather in the Vatican. The election starts with a special Mass at St. Peter’s Basilica, followed by the cardinal electors-those under the age of 80-taking an oath of secrecy. They are then secluded within the Sistine Chapel, cut off from all outside communication until a new Pope is chosen. Voting is conducted in secret, typically up to four times a day, and a candidate must receive a two-thirds majority to be elected. The results of each ballot are signaled by smoke rising from the Sistine Chapel chimney: black smoke indicates no Pope has been elected, while white smoke signals that a new Pope has been chosen. Once elected and having accepted the office, the new Pope is introduced to the public from the balcony of St. Peter’s Basilica.
The most recent development in conclave history occurred in May 2025, when, for the first time, a Pope was elected from the United States: Robert Francis Prevost, who took the name Pope Leo XIV. This conclave was attended by 133 cardinals and lasted for three rounds of voting over two days. Pope Leo XIV, born in Chicago in 1955, is known for his global experience, including serving as a Bishop in Peru and as Archbishop of Chicago. This historic event marks the first time a Pope has come from the United States and only the second time from the Americas, following Pope Francis from Argentina.
