Eugenius IV (1383–1447)

Pope from 1431 until his death in 1447, Eugenius was born Gabriele Condulmer, the son of a Venetian merchant. At the age of twenty-four, Pope Gregory XII, his uncle, appointed him as bishop of Siena. When the people of Siena opposed him as an outsider, Condulmer resigned to become the Vatican treasurer. He won election as pope after the death of Martin V in 1431. This event took place soon after the opening of the Council of Basel, a meeting of bishops, monks, and religious scholars who sought to reform the church and represented a serious challenge to the pope's authority. Eugenius issued a papal bull (decree) dissolving the council in December 1431, but the council members responded by demanding that he appear before the council and recognize its authority over him. In 1433, faced with rising opposition in northern Europe and a budding Protestant movement in Bohemia, the pope withdrew his bull and acknowledged the council as valid.

Eugenius took an active role in the wars and rivalries of northern Italy. He supported Florence and Venice in their struggle with Milan; to counter this, Milanese troops attacked papal territory in central Italy. The defeat of the pope's army set off a violent uprising in Rome, which Eugenius escaped by disguising himself as a monk and having himself rowed to safety down the Tiber River to the port of Ostia. The pope settled in the town of Bologna while, over the next few years, his armies reconquered the Papal States. In 1438 Eugenius convened another council at Ferrara, where he placed a ban of excommunication on the authorities meeting at Basel. They then accused the pope of heresy, announced him deposed from his throne, and elected the antipope Felix V. The rival popes made peace in 1442, after which Eugenius returned to Rome and persuaded the princes of Germany to support him. After many years of bitter struggle, he had prevailed over the conciliar movement that presumed to be the final authority in church matters.