Benedict XIII, born Pedro Martínez de Luna, (b. Illueca, Aragon, 1328; d. Peñíscola, near Valencia, 1423) was an Aragonese, and is considered by many Roman Catholics an Antipope.
Pedro de Luna was born at Illueca in Aragon (part of modern Spain) in 1328. He belonged to the de Luna family, who were part of the Spanish noblility. He studied law at the University of Montpellier, where he obtained his doctorate and later taught canon law. His knowledge of canon law, noble lineage and austere way of life won him the approval of Pope Gregory XI, who appointed de Luna to the position of Cardinal Deacon of Santa Maria in Cosmedin on 30 December 1375.
In 1377 Pedro de Luna and the other cardinals returned to Rome with Pope Gregory, who had been persuaded to leave his papal base at Avignon by Catherine of Siena. After Gregory's death on 27th March 1378 the people of Rome feared that the cardinals would elect a French pope and return the papacy to Avignon. Consequently a large number of people rioted and laid siege to the cardinals, insisting that they elect an Italian pope. The conclave duly elected Bartholomew Prignani, the Archbishop of Bari, as their new pope Urban VI on 9th April, but the new pope proved to be intractably hostile to the cardinals. Therefore the cardinals reconvened at Fondi in September 1378 declared the earlier election invalid and elected Robert of Geneva as their new pope. Robert assumed the name Clement VII and moved back to Avignon.
Pedro de Luna was a supporter of Robert of Geneva, the Avignon Pope Clement VII, throughout his reign, and de Luna was unanimously elected by a conclave of twenty-four cardinals at Avignon on September 28, 1394, following the death of Clement VII on September 16. The conclave consisted of eleven French cardinals, eight Italians, four Spaniards and one cardinal from Savoy. On the death of Urban VI in 1389 the Roman College of Cardinals had chosen Boniface IX; the election of Benedict therefore perpetuated the Western Schism. At the start of his term of office, de Luna was recognized as pope by the kingdoms of France, Scotland, Sicily, Castile, Aragon, Navarre, and Portugal. In 1396 Benedict sent Sanchez Muñoz, one of the most loyal members of the Avignon curia, as an envoy to the Bishop of Valencia to bolster support for the Avignon papacy in Spain.
However, in 1398 the French church withdrew their allegiance from the Avignon papacy. Benedict was abandoned by seventeen of his cardinals, with only five remaining faithful to him. An army led by Geoffrey Boucicaut, brother of the illustrious marshal, occupied Avignon and started a five year siege of the papal palace in 1398, which ended when Benedict managed to escape from Avignon on March 12, 1403 and seek shelter in territory belonging to Louis II of Anjou.
By this stage, Benedict's authority was no longer recognized in France, Portugal and Navarre, but he was acknowledged as pope in Scotland, Sicily, Aragon and Castile. After the Roman Pope Innocent VII died in 1406, the newly elected Roman pope, Gregory XII, started negotiations with Benedict, suggesting that they both resign so a new pope could be elected to reunite the Catholic Church. When these talks ended in stalemate in 1408, the French king, Charles VI, declared that France was neutral to both papal contenders. Charles helped to organize the Council of Pisa in 1409. This council was supposed to arrange for both Gregory and Benedict to resign, so that a new universally recognized pope could be elected. However, since both Benedict and Gregory refused to abdicate, the only thing that was achieved was that a third candidate to the Holy See was put forward: Peter Philarghi, who assumed the name Alexander V.
In 1415 the Council of Constance brought this state of affairs to an end. Gregory XII and Baldassare Cossa, who had succeeded Philarghi as the Pisan papal contender in 1410 and had assumed the name John XXIII, both agreed to resign. Benedict, on the other hand, refused to stand down, so he was declared a schismatic and excommunicated from the Catholic Church by the Council of Constance on July 27, 1417. Benedict, who had lived in Perpignan from 1408 to 1417, now fled to the castle at Peñiscola near Valencia in Spain. He still considered himself the true pope, but his claim was now only recognised in the kingdom of Aragon, where he was given protection by King Alfonso V. Benedict remained at Peñiscola from 1417 until his death there on May 23, 1423.
The day before his death, Benedict appointed four cardinals of proven loyalty to ensure the succession of another pope who would remain faithful to the now beleaguered Avignon line. Three of these cardinals met on 10 June 1423 and elected Sanchez Muñoz as their new pope, with Muñoz assuming the papal name of Clement VIII. The fourth cardinal, Jean Carrier, the archdeacon of Rodez near Toulouse, was absent at this conclave and disputed its validity, whereupon, Carrier, acting as a sort of one man College of Cardinals, proceeded to elect Bernard Garnier, the sacristan of Rodez, as pope, with Garnier taking the name Benedict XIV.