Every thing seemed arranged, when unexpected obstacles arose. On the one hand, Charles of Valois, having neither dominions nor crown, obstinately resisted the transfer of his imaginary kingdom; on the other, the Sicilians declared they would die to a man rather than acknowledge the sovereignty of the house of Anjou. They summoned Don Jaime to renounce his project, and when he persisted in it, they raised to the throne the Infante Frederick, at first with the title of Lord of Sicily, afterwards with that of King. This prince proved worthy of the national choice. In vain did Boniface VIII. assail him in turn with flattery and menace; the new king of Sicily remained faithful to his people. By a strange concurrence of circumstances, he found himself opposed in arms to his brother Jaime of Arragon, now the ally of his father-in-law, Charles II., who had recovered his liberty and returned to his dominions. In spite of his own and his subjects' valour, Frederick III. was at first nearly overcome. The house of Anjou would have reconquered Sicily, but for the defection of the fickle King of Arragon, who abandoned his allies and returned home, carrying with him the contempt of all parties. After various changes of fortune, a definitive treaty of peace was concluded between the belligerents, under the auspices of Rome. By its conditions, Frederick III. was to retain the crown of Sicily for his life, with the title of King of Trinacria, invented to avoid infringement on the rights of Charles II., who kept the title of King of Sicily, with the reversion of the dominions for himself and his direct heirs, after the death of Frederick, who married Eleanor, youngest daughter of Charles. The basis of this treaty was manifestly unstable, its very letter was soon effaced: and Frederick, disdaining the singular title of King of Trinacria, soon resumed his rightful one. There were thus two kings of Sicily, on this and that side the straits, and from that period dates the term, the Two Sicilies.