Western Schism

The Western Schism, also known as the Great Divide, the Great Occidental Schism, the Schism of 1378, or the Great Western Schism (Latin: Magnum schisma occidentale, Ecclesiae occidentalis schisma), was a split within the Catholic Church lasting from 20 September 1378 to 11 November 1417, in which bishops residing in Rome and Avignon simultaneously claimed to be the true pope, and were eventually joined by a line of Pisan claimants in 1409. The event was driven by international rivalries, personalities and political allegiances, with the Avignon Papacy in particular being closely tied to the French monarchy.

The papacy had resided in Avignon since 1309, but Pope Gregory XI returned to Rome in 1377. The Catholic Church split in September 1378, when, following Gregory XI's death and Urban VI's subsequent election, a group of French cardinals declared his election invalid due to intimidation and violence and, in the presence of three Italian cardinals, elected Clement VII, who claimed to be the true pope. As Roman claimant, Urban VI was succeeded by Boniface IX, Innocent VII and Gregory XII. Clement VII was succeeded as Avignon claimant by Benedict XIII.