Complex sentence: He was assigned to handle the case against Robert de Mauvoisin He was named Bishop of Riez on 31 March 1318, and after Mauvoisin resigned he was granted the Archbishopric of Aix on 11 September 1318, two days after the forced resignation of his predecessor.
Split into simpler sentences: He was assigned to handle the case against Robert de Mauvoisin, and was named Bishop of Riez on 31 March 1318. After Mauvoisin resigned he was granted the Archbishopric of Aix on 11 September 1318, two days after the forced resignation of his predecessor.