Whenever a pope steps down or passes away, a conclave is held to select the next leader of the Catholic Church. This secretive gathering of cardinals holds incredible power — not just to choose a pope, but potentially to change (or even endanger) the Church itself. One historic conclave nearly split the Vatican forever, threatening the very existence of Catholicism as we know it.
The conclave is a centuries-old tradition where cardinals gather in strict secrecy to elect a new pope. While many conclaves are uneventful, some have sparked major crises. You may have heard of the longest one in history, which dragged on for over three years because cardinals couldn’t agree on a candidate. Eventually, the frustrated citizens of Viterbo locked the cardinals in and even started removing the roof to force a decision! But that’s a story for another time.
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The 1378 Conclave: When the Church Faced Its Greatest Threat
The most dangerous conclave happened in 1378, after the death of Pope Gregory XI. Sixteen cardinals met at St. Peter’s Basilica in Rome under intense public pressure. The people demanded a Roman — or at least an Italian — pope.
They elected Bartolomeo Prignano of Bari, who took the name Urban VI. But instead of unifying the Church and state (as was crucial at the time), Urban VI clashed fiercely with King Charles V.
Soon, 12 of the 16 cardinals who had elected him fled Rome for Naples (then called Fondi). There, they declared the election invalid and chose a new pope: Clement VII.
A Church Divided For Nearly 40 Years
Urban VI responded by excommunicating the rebel cardinals and appointing 20 new ones. Suddenly, the Catholic Church had two popes — a crisis that became known as the Western Schism.
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From 1378 to 1417, Europe was religiously and politically divided. Different kingdoms backed different popes. Spain even named its own pope, Benedict XIII, deepening the chaos.
The Schism might have lasted indefinitely if not for the German emperor Sigismund. In 1414, at the Council of Constance, he persuaded Church leaders to depose all three rival popes and elect a single new one.
That pope was Martin V, who finally restored unity to the Catholic Church.
Without the Council of Constance, the Church would have likely remained divided, spawning even more branches and interpretations of Christianity. The Vatican might not hold the global influence it does today.
This article was originally written in Spanish by Fernando Eslava in Cultura Colectiva.