What happens when no one is sure who the Pope is? What happens if there are two fellows—or even three—parading around in tiaras and extending the foot to be kissed—who is the real pope? How can you tell? How do you know? What happens when you have One Pope in Delia, Kansas and another in Springdale, Washington? How can you tell who the real pope is? O wait, the Pope in Springdale died. OK, so we have a Pope in Delia Kansas, and one in Hertfordshire. (That’s in England.) Oh—and then there seems to be two more in Brussels. And apparently thee is one each in Lucerne and Angoulême. What’s a Catholic to do? OK, we will leave aside those who have arranged their own conclaves in the back room of a store or whom Jesus personally ordained, consecrated, and crowned in a mystical vision and focus on just three popes: one in Rome; one in Avignon; and one in Pisa. That is the situation in which the Church found itself in the fifteenth century, specifically in 1414 when a (Ecumenical) Council opened in Konstanz, Switzerland. The King of Hungary and Holy Roman Emperor Sigismund had summoned the bishops to end a schism which saw three men—all with somewhat sound claims (certainly sounder than the formerly mentioned visionaries and psychotics) to be the legitimate heir of Peter the Apostle.
You have a Roman claimant, Gregory XII, who traced his lineage back through Urban VI, who was elected pope upon the death of Gregory XI in 1378. Gregory was the pope who moved the papacy back to Rome at the end of the Avignon papacy. He was duly elected by the Cardinals—all the Cardinals, French and Italian—and his coronation was carried out with great detail so there would be no doubt of his legitimacy. Sound like the Pope, doesn’t he?
Problem—five months later the French Cardinals met at Fondi—a town between Rome and Naples—and elected one of their own, Robert of Geneva Pope, claiming that the election of Urban was invalid because they had been coerced by the Roman mob into choosing an Italian pope. The charge was true and they had a point. Of course, the fact that the King of France put the French Cardinals up to this colors the story a bit too. But if the Cardinals were coerced by fear and the election were not to be a free election, would it be valid? This is not an abstract question. There are some fringe groups in the Church that claim that the 1958 and 1963 conclaves were prevented under threats from electing the late Cardinal Giuseppe Siri (or that Siri was elected and prevented from taking the papal office by outside threats).
How do you solve the problem of who is pope when you have two of them? Who has the authority to decide? To break the stalemate? The theology faculties of various universities including Paris (at the time, the leading theology faculty of Europe), leading theologians of the day (including Jean de Charlier de Gerson and Conrad of Gelnhausen), the town councils of cities across Europe, crowned heads, agreed—it would take an Ecumenical Council to cut the Gordian knot. A delegation of Avignon-obedience cardinals met with a delegation of Roman-obedience cardinals and agreed upon a Council. Their respective popes weren’t happy and each called his own rival Council: The Avignon Benedict XIII for Perpignan and the Roman Gregory XII for Aquilea. Almost no one went to Aquilea or Perpignan, but 22 cardinals, 80 bishops, proxies for another hundred bishops, 87 Abbots, 41 priors or general superiors of religious orders, and 300 doctors of theology or doctors of canon law showed up in Pisa where they proceeded to declare both Gregory and Benedict deposed and elected Alexander V as pope. The story is a little more complicated, but we will save it for another day. Neither Gregory nor Benedict would abdicate, so now there were three popes.
It ended up with Sigismund calling another Council—this one for Konstanz—and the results were somewhat similar except that this time the Roman claimant, Gregory, sent proxies who convoked the council in his name and then submitted—again in his name—his abdication. It was a clever, and I suspect sincere, move for it preserved the authority (and thus the legitimacy) of the Roman line even though it lost the papacy for Gregory himself. In other words, by not refusing to acknowledge the legitimacy of the Council but imposing his “convocation” of it over the Emperor’s original summons, it forced the Council into acknowledging the authority of the Pope—and in this case, the Roman Pope—to call a Council. It thus disposed the Council to recognize the legitimacy of the Roman claim as neither the Avignon nor Pisan pope had given their authority to holding the assembly. By abdicating Gregory did not allow the Council to depose a pope; and by abdicating while his rivals would not, he forced the Council to depose them which, again, asserted the legitimacy of the Roman line.
It sounds like it all wrapped up neatly. Unfortunately that is not quite true. They always say that the winners write the history books, but they are wrong. Whoever writes the history book is the winner. The war is not won on the field, but in the telling of the story. The Roman popes told the story pretty much as I have. The pope convoked the Council. The pope abdicated. A new pope was elected. But many of the Council participants told the story differently. They had gathered in Council on the initiative of the Emperor at the request of the Church (not the pope, but the bishops, the theologians, the universities, the towns, and others who had petitioned the Emperor for a Council), and in Council they accepted the abdication of the Roman claimant and deposed the two refusniks (to use a term from the late twentieth century), and they elected a new pope. Note—the cardinals did not elect the pope—the council did. The conclave consisted of the cardinals present and thirty representatives of the Council.
Konstanz ended and everybody went home but some went home with the opinion that a Council could depose and/or elect a pope. In this case, the pope was not the highest authority in the Church. Others went home with the idea that it takes a pope to convoke a Council and a pope can resign but only anti-popes, that is false claimants, can be deposed. This argument would go on for a long time—and would cause confusion and division at the time of Luther and the Protestant Reformations.