When Joan died in 1358, Peter made his will (dated 10 November 1358), renounced his counties in favour of his sons and entered the
Franciscan (12 November). His decision to join the Franciscans greatly enhanced that order's standing in the Crown of Aragon. His retirement from worldly affairs, however, was only partial. In 1364–1365, with Peter IV unable to leave Aragon, the Franciscan left his convent to assist Peter IV's young son, the future
John I, in the defence of Valencia against a Castilian invasion. Using his contacts at Avignon, the Franciscan helped arrange in 1365 for the
free company of soldiers under
Bertrand du Guesclin, the so-called
White Company, to assist Count
Henry of Trastámara in his revolt against Peter of Castile. Peter's final years were occupied by his great concern for the peace and unity of the church. He was highly regarded in the
papal curia. He penned his
Revelations, a prophetic tract in a
Joachimite vein and influenced by
Jean de Roquetaillade, in an effort to end the
"Babylonian captivity" of the papacy in Avignon. He was forced to defend his work before Pope
Urban V in Avignon, but it was condemned in 1365. It was during this stay at Avignon that he met
Francesc Eiximenis. In 1369, Peter's son-in-law, King Peter of Cyprus, was assassinated. In June 1371, Pope
Gregory XI wrote to
John of Lusignan, the regent for Peter's grandson, King
Peter II, informing him that the elder Peter was on his way to Cyprus and that the crown should pay his expenses. The pope also ordered the
Knights of Rhodes to render Peter assistance. There is, however, no record confirming that Peter of Ribagorza ever got to Cyprus or played any role in his grandson's minority. He was certainly at the papal
curia in February 1373, when his daughter sent
John Laskaris Kalopheros there to convey a message to him. In August, Alfonso Ferrand was also instructed to bring a message to Peter. Eleanor sought through Peter to gain papal support for the
Genoese intervention that would unseat the regent. Eleanor's machinations involving her father were recorded by
Leontios Makhairas. During the
Western Schism that resulted in 1378, Peter broke with the king of Aragon and openly supported the Roman pope,
Urban VI. The future John I, using secret channels, managed to block Urban from making Peter a
cardinal in 1380. He died at
Pisa on 4 November 1381 while on his way to Rome. He was buried in the local Franciscan convent, but his body was moved to the in 1391. ==Children==