The longest time to elect a new pope after the death of the previous one amounted to almost three years. This happened after the death of Clement IV in 1268. Of course, such a situation was bad for the Catholic Church, because it was left leaderless during these three years. During the election, three cardinals died and one resigned. The reason why the papal elections were so prolonged was because there were conflicting parties in the College of Cardinals. They were about the same strength, which resulted in a stalemate.
The election was held in Viterbo, not far from Rome, because there was a regulation that the elections must be held in the city where the previous pope died. After a long wait, in order to force the Cardinals to finally make a decision, the citizens of Viterbo allegedly locked them in the local palace and limited their meals. When that did not help, according to the legend, the citizens even removed the roof of the building, so the Cardinals would have no protection from the elements.
The decision by the cardinals was made in 1271. Tedaldi Visconti, who took the name of Gregory X, was elected. In order that such an awkward situation with delaying the election would never be repeated, a decree was introduced on the so-called “conclave”.
The word conclave comes from the Latin word for “locked”. Namely, in future the cardinals were “locked up” in a confined space until they made a decision on the election of the new pope. According to the model of the citizens of Viterbo, the cardinals even had their daily quantity of food limited during the future conclaves. These conclave regulations were introduced precisely by the aforementioned Pope Gregory X (now a Blessed of the Catholic Church) in a papal bull “Ubi periculum” in 1274.
The same Pope is also known through the story of Marco Polo. Namely, the Mongol ruler Kublai Khan asked Gregory X to send him missionaries. The Pope sent young Marco Polo, his father Niccolò and his uncle Maffeo. The same Pope Gregory X died on this day in 1276, and played a significant role in history.