Antipope the chief of a party who causes a schism in order to dethrone a pope lawfully elected, and to assume his place. Twenty-seven such illegal competitors for the papacy are reckoned from the third century to the present time, viz.:
1. Novatian, who disputed the see with Cornelius, in 251.
2. Ursinus, with pope Damasns, in 367.
3. Eulalius, with pope Boniface I, in 418.
4. Laureutius, with pope Symmachus, in 498.
5. Dioscorus, the deacon, with pope Boniface II, in 580.
6. Peter and Theodore, with pope Conon, in 686.
7. Theodore and Pascal, with pope Sergius, in 687.
8. Theophylact, with pope Paul I, in 757.
9. Constantine, forcibly held the see thirteen months after the death of Paul.
10. Philip, a monk. declared pope by the faction of Waldipertus, in -768.
11. Zosimus, disputed the see with pope Eugenius II, in 824.
12. Anastasius, with pope Benedict III, in 855.
13. Sergius, with pope Formosus, in 891.
14. Boniface, after the death of Formosus, in 896, driven out by pope Stephen VII.
15. Leo, disputed the see with popes John XII and Benedict V, in 955 and 964.
16. Gregory, with pope Benedict VIII.
17. Silvester III and John XXII contested the see with pope Benedict IX; all three resigned in favor of Gregory VI, in 1044.
18. Mincius (styled Benedict), contested the see with pope Nicholas II, in 1059.
19. Cadolaus (Honorius II), with Alexander II, 1061.
20. Guibert of Ravenna (Clement III), with Gregory VII, in 1073.
21. Theobald (Celestine II), with Honorius II, in 1124.
22. Peter (Anacletus II), with Innocent II, in 1130.
23. Octavianus (Victor IV), with Alexander III, in 1159.
24. Peter (Nicholas V); while the see was in France pope John XXII arrested him.
25. Robert (Clement VII), began the great schism in 1378, and held the' see at Avignon, against popes Urbani VI and Boniface IX.
26. Peter of Luna (Benedict XI, XII, or XIII, according to different writers), held the see thirty years at Pehiscola, Spain, against Boniface IX and his successors.
27. Giles de Mufioz, a Spaniard (Clement VIII), opposed pope Martin V five years, viz. from 1424 to 1429.