In 1282, Charles lost control of the island of Sicily in the violent massacre known as the Sicilian Vespers. The Sicilians had elected Peter III of Aragon as their king and sought papal confirmation, in vain, though they were willing to reconfirm Sicily as a vassal state of the papacy. Martin IV used all the spiritual and material resources at his command against the Aragonese in order to preserve Sicily for the House of Anjou. He excommunicated Peter III, declared his kingdom of Aragon forfeit, and ordered a crusade against him, but it was all in vain.