Roman Catholic Diocese of Fiesole Tags: Clerical Administrative Region, Diocese.The Diocese of Fiesole (Latin: Dioecesis Fesulanus) is a Roman Catholic diocese in Tuscany central Italy whose episcopal see is the city of Fiesole. It is a suffragan of the Metropolitan Archbishopric of Florence. thumbnail area (km2) 1.3e+09 country Italy Established 1st Century province Roman Catholic Archdiocese of Florence Learn more... Loading...