Blessed Gregory X
Teobaldo Visconti · 1271 – 1276
Elected after the longest conclave in history, he reformed the election process and convened the Second Council of Lyon.
Teobaldo was an Italian archdeacon on crusade in the Holy Land when he learned he had been elected pope — after a conclave that lasted nearly three years. That experience drove him to reform papal elections: he instituted the conclave system, requiring cardinals to be locked in seclusion with progressively reduced food until they chose a pope. He also convened the Second Council of Lyon in 1274, which briefly reunited the Eastern and Western churches.
Why He Matters
Gregory X's conclave rules — lock the cardinals up and cut their meals until they decide — were born from the absurdity of a three-year vacancy. The basic structure he created still governs how popes are elected.