The aged Giovanni Gaetano Orsini was elected Pope Nicholas III, to the dissatisfaction of Charles I of Naples (whose interests were supported by the three French cardinals).

[5] The breakthrough in the deadlock came when Charles I replaced Orso Orsini, the podestà of Viterbo, with Riccardello Annibaldi, who proceeded to burst into the election and arrest and remove the Orsini cardinals, allowing the pro-Angevin faction and the Aldobrandeschi partisans to push through the election of Simon de Brion, the favored candidate of Charles, as Pope Martin IV.

[5] Giordano, the leader of the anti-French faction, and his nephew Matteo, were imprisoned, actions that ensured that the new French pope would find no welcome in returning to Rome.

As a result of the interdict, and of the hostility of the city of Rome to a pontiff favorable to the Angevins, Martin IV was compelled to move the Roman Curia to Orvieto, where he was crowned on March 23, 1281.

[3] Among the first acts of Martin IV were to remove from prominent positions the Orsini cardinal-nephews of his predecessor, Nicholas III, and to replace them with French and pro-French candidates.