Pisa, Council of definition of Pisa, Council of in the Free Online Encyclopedia.

Pisa, Council of, 1409, unrecognized council of the Roman Catholic Church. It was summoned to end the Great Schism (see Schism, Great Schism, Great, or Schism of the West, division in the Roman Catholic Church from 1378 to 1417. There was no question of faith or practice involved; the schism was a matter of persons and politics.
..... Click the link for more information. ) by members of the colleges of cardinals of the two rivals, Gregory XII (in Rome) and Benedict XIII (Pedro de Luna Luna, Pedro de (pā`thrō dā l
..... Click the link for more information. , in Avignon). The plan was to depose both men claiming to be pope and elect a new one. The council had a wide international attendance. It declared both popes to be heretical and schismatic and therefore not popes; the cardinals proceeded to elect Pietro Cardinal Philarghi as Alexander V. This move served to complicate the schism with a third claimant rather than to dissolve it. The council first gave quasi-official expression to the conciliar theory, i.e., that councils are supreme in the church, a notion that became prominent again at Constance and at Basel (see Constance, Council of Constance, Council of, 1414–18, council of the Roman Catholic Church, some of its sessions being reckoned as the 16th ecumenical council. It was summoned to end the Great Schism (see Schism, Great ), in which three men were claiming to be pope— Gregory
..... Click the link for more information. ; Basel, Council of Basel, Council of, 1431–49, first part of the 17th ecumenical council in the Roman Catholic Church. It is generally considered to have been ecumenical until it fell into heresy in 1437; after that it is regarded as an anticouncil.
..... Click the link for more information. ). The lack of recognition toward the council rests on several features; e.g., most of the cardinals involved owed their creation to popes whom they declared to be holding office illegally.