During the 14th century, the papacy came under greater and greater influence of the French kings. This was a counter-balance to the influence of the Italian cardinals over the affairs of the church. In 1310, Clement V, a frenchman, moved the papal residence to Avignon, France. He and his successors remained there for most of the century. The papal states in Italy were ruled by a commission of three cardinals. Over the years, this produced near anarchy in central Italy, with Italians demanding the Pope return to Rome. This dissent reached a climax in 1378 with the death of Pope Gregory XI--the last of the French popes. Two popes were elected to succeed Gregory XI: Urban VI, who governed from Rome, and Clement VIII who governed from Avignon.
The election of Urban VI was marred with riots in Rome, where the conclave of cardinals took place. Rumor has it that a Roman mob broke into the church and threatened the cardinals if they did not elect a Roman pope. The cardinals then elected Urban VI on April 7, 1378. But, after his election, Urban VI turned from a quiet monk to an overbearing leader. Regretting their decision, the cardinals retired to the city of Fondi, where they declared the election of invalid and proceeded to elect Clement VII pope on September 20 of the same year. The world now had two popes.
The Sacred College split, and so did Europe: Urban VI was supported by the rulers of England, Ireland, Germany, Flanders, the northern Italian cities, Poland and Hungary; Clement VII had to support of Aragon, Castile, Navarre, Portugal, Scotland, Naples and France. This is the start of the Western Schism.
Wenceslas, who is elected Holy Roman Emperor in 1378, spends most of his energies trying to end the Western Schism, which has continued through a succession of popes. Clement VII dies in Avignon in 1394 and is suceeded by Benedict XIII (28 Sept 1394). In Rome, Urban VI dies in 1389, and is suceeded by Boniface IX (2 Nov 1389 - 1 Oct 1404). Boniface reclaims the support of the Ladislas, King of Naples. Boniface IX, suspecting Hungary of defecting to the pope of Avignon, incites Ladislas to invade Hungary and claim the throne. Ladislas is defeated shortly after his arrival in Dalmatia.
Boniface IX is succeeded by Innocent VII (17 Oct 1404 - 6 Nov 1406), during whose reign the citizens of Rome revolt. The revolt is suppressed by Ladislas of Naples, who retains his troops in the papal city. He only withdraws when Innocent VII threatens him with excommuniciation. Innocent VII is succeeded by Gregory XII, who is pope from 30 Nov 1406 to 4 July 1415. During Gregory's reign serious efforts to end the Western Schism begin, and finally, suceed.
Gregory's first effort at ending the schism is by calling both Roman and Avignon cardinals to a Council in Pisa. The council meets from 25 March 1409 to late June or early July of 1409. To end the schism, the council deposes both Gregory XII and Benedict XIII, and elects Alexander V (26 June 1409 - 3 May 1410) in its last sessions. Both the Roman and Avignon popes refuse to accept the actions of the council, so Alexander reigns in Pisa. After his death, the cardinals in Pisa elect John XXIII pope, who serves from 24 May 1410 - 29 May 1415.
After the fiasco at Pisa, the Diet of the Holy Roman Empire deposes Wenceslas IV in 1411, and elects his brother, Sigismund, who is both Margrave of Brandenburg and King of Hungary, as King of the Romans. Sigismund vows to end the schism, and persuades Gregory XII to call another council, this time in Germany. The Council of Constance opens 5 Nov 1414 with three purposes:
The council is successful in ending the Western
Schism. First, John XXIII is forced to
resign on 29
May 1415. Gregory XII then follows on
the 4th of July. But, Benedict XIII
refuses. So the council negotiates with
his supporters, and at the treaty of Narbonne on 13 Dec 1415, the
Spanish
states, Aragon, Castile, and Navarre, renounce their support of
Benedict XIII
and commit to support the actions of the council. With
only French support, Benedict XIII flees Avignon for a
remote monastery in Aragon. He is
finally deposed by the council on 26 July 1417. Gregory
XII dies 18 Oct 1417.
The council then elects Martin V pope (11 Nov 1417 - 20 Feb
1431). Martin V dissolves the
Council of Constance
on 22 April 1418. John XXIII and
Benedict XIII submit to Martin V on 23 June 1419, and the Western
Schism was
over.