An "antipope" is defined as a false claimant to the papal see in opposition to a pope who has been canonically elected. Deciding who is an antipope and who is a real pope is not always clear-cut.
Benedict V - May to June, 964
Known as Grammaticus for his learning, Benedict V was elected after Emperor Otto had forcibly deposed John XII and put Leo VIII in his place. Otto was infuriated that the clergy had elected another pope and may have convinced (or coerced) Benedict to declare himself an intruder. Benedict was degraded to deacon and brought back to Germany with Otto, where he appears to have lived comfortably until his death a year later. Either Benedict or Leo may be considered an antipope, but since Benedict was duly elected and Leo was chosen by the emperor, Benedict is often considered a true pope.
Benedict (X) - Antipope - 1058-1059
This Benedict was installed on the papal throne by the Tusculanis in April of 1058, but in December the clergy elected Nicholas II, and in January of 1059 Benedict was expelled and imprisoned. The anti-papacy of Benedict X is important, because it prompted Nicholas to enact new laws concerning papal elections and establish an electoral body that would become the College of Cardinals. Benedict X died a prisoner in the monastery of Sant'Agnese.
Even though this pope is officially considered an antipope, the next pope named Benedict did not repeat the number X, and was instead called Benedict XI.
Benedict (XIII) - Antipope - 1394-1423
In 1378 the Western Schism began when the cardinals at Avignon refused to accept the return of the papacy to Rome and elected Clement VII in opposition to the Roman Urban VI. Benedict allied with Clement, and on Clement's death he was elected by the Avignon cardinals with the understanding that he would volunarily abdicate if that would help end the schism. But when approached a few years later by French princes who had supported him and asked him to abdicate, he refused. Most of his cardinals deserted him, and the papal palace in Avignon was besieged by French forces in 1398. Five years later, Benedict escaped the palace, rallied his cardinals and won back the support of France.
Benedict then sought to negotiate a compromise with the pope in Rome (Gregory XII), but nothing came of it, and the French declared themselves neutral in the papal dispute. In 1409, the Council of Pisa attempted to put an end to the schism by deposing both popes and electing a third (Alexander V), but Benedict refused to submit. He took refuge in his castle at Peñíscola in 1415, and when the Council of Constance officially pronounced him deposed in 1417, he lost all government recognition, with the exception of Scotland and Armagnac, France. Still, he maintained that he was the rightful pope until his death in 1423, and even created new cardinals.
Benedict (XIV) - Antipopes - 1425-1433(?)
When the antipope Benedict XIII died, King Alfonso V of Aragon, wanting to prolong the schism, got the (very small) college of cardinals Benedict XIII had created to elect a new pope: Clement VIII. But one cardinal from Benedict's antipapacy who had not been invited to Alfonso's conclave, Jean Carrier, called his own conclave and elected Bernard Garnier, who became Pope Benedict XIV, an antipope to an antipope. Benedict XIV was so secretive that virtually no one but Carrier knew where he was living. He ended his reign in 1430, making a cardinal of a certain Jean Farald before he left.
Three years later Cardinal Carrier was captured and imprisoned in Gascony and, upon the recent death of Garnier, he was "elected" pope by Cardinal Farald. Carrier also called himself Benedict XIV, and he proclaimed himself the rightful pope, even though he had been elected by one man. He died in prison at some unknown date.
Next: Post-Medieval Popes
