Pope Gregory XI was Pierre Roger de Beaufort, a Benedictine, archbishop of Rouen and pope from 1370 to 1378, succeeded pope Urban V; he was the last pope in residence at Avignon before the Great Schism that followed the election of his successor. Froissart is mistaken though. Gaston died in 1381: the pope would have been Clement VII, the first pope from the Clementine party to continue to reside in Avignon.
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