| Year | From | To | 
|---|
| 1980 | Mission "Sui Iuris" of Kalumburu, Australia | Suppressed | Diocese of Broome, Australia | Territory Added | 
| 1982 |  |  | Patriarchal Exarchate of Bassorah e Golfo (Syrian), Iraq | Erected | 
| 1984 |  |  | Orden de los Hermanos de Belén | Restored | 
| 1988 |  |  | Fraternity of Saint Vincent Ferrer | Approbation | 
| 1988 |  |  | Servants of Jesus and Mary | Founded | 
| 1989 |  |  | Titular See of Bistue | Established | 
| 1989 |  |  | Titular See of Bossa | Established | 
| 1989 |  |  | Titular See of Buleliana | Established | 
| 1989 |  |  | Titular See of Canapium | Established | 
| 1989 |  |  | Titular See of Castellum Titulianum | Established | 
| 1989 |  |  | Titular See of Catrum | Established | 
| 1989 |  |  | Titular See of Cebarades | Established | 
| 1989 |  |  | Titular See of Enera | Established | 
| 1989 |  |  | Titular See of Macon | Established | 
| 1989 |  |  | Titular See of Mattiana | Established | 
| 1989 |  |  | Titular See of Paria in Proconsolare | Established | 
| 1989 |  |  | Titular See of Pia | Established | 
| 1989 |  |  | Titular See of Pocofeltus | Established | 
| 1989 |  |  | Titular See of Taddua | Established | 
| 1989 |  |  | Titular See of Tagase | Established | 
| 1989 |  |  | Titular See of Tamazeni | Established | 
| 1989 |  |  | Titular See of Vertara | Established | 
| 1989 |  |  | Titular See of Wiener Neustadt | Established | 
| 1989 |  |  | Titular See of Bulna | Established | 
| 1989 |  |  | Titular See of Buslacena | Established | 
| 1989 |  |  | Titular See of Cibaliana | Established | 
| 1989 |  |  | Titular See of Murcona | Established | 
| 1989 |  |  | Titular See of Musti in Numidia | Established | 
| 1989 |  |  | Titular See of Sitipa | Established | 
| 1989 |  |  | Titular See of Ausana | Established | 
| 1989 |  |  | Titular See of Ausuaga | Established | 
| 1989 |  |  | Titular See of Turuda | Established | 
| 1989 |  |  | [Patriotic Diocese of Shanba, China] | Erected | 
| 1989 |  |  | Franciscan Brothers of the Third Order Regular of Brooklyn | Approbation | 
| 1990 |  |  | Franciscan Friars of the Renewal | Founded | 
| 1990 |  |  | Institut du Christ Roi Souverain Prétre | Founded | 
| 1991 | Patriarchal Vicariate of Turkey (Syrian) | Elevated | Patriarchal Exarchate of Turkey (Syrian) | Elevated | 
| 1991 | Patriarchal Vicariate of Jerusalem (Chaldean), Palestine | Elevated | Patriarchal Exarchate of Jerusalem (Chaldean), Palestine | Elevated | 
| 1992 | Patriarchal Vicariate of Egypt and Sudan (Melkite Greek) | Elevated | Patriarchal Exarchate of Egypt and Sudan (Melkite Greek) | Elevated | 
| 1992 | Patriarchal Vicariate of Jerusalem {Gerusalemme} (Melkite Greek), Palestine | Elevated | Patriarchal Exarchate of Jerusalem {Gerusalemme} (Melkite Greek), Palestine | Elevated | 
| 1992 |  |  | Chemin Neuf Institute | Founded | 
| 1992 | Diocese of Tuy-Vigo, Spain | Name Changed | Diocese of Tui-Vigo, Spain | Name Changed | 
| 1993 |  |  | Canons Regular of the Congregation of Saint Victor | Approbation | 
| 1993 |  |  | [Patriotic Diocese of Langfang, China] | Erected | 
| 1994 |  |  | Servants of Jesus and Mary | Approbation | 
| 1995 |  |  | Titular See of Alton | Established | 
| 1995 |  |  | Titular See of Grass Valley | Established | 
| 1995 |  |  | Titular See of Jamestown | Established | 
| 1995 |  |  | Titular See of Kearney | Established | 
| 1995 |  |  | Titular See of Lead | Established | 
| 1995 |  |  | Titular See of Leavenworth | Established | 
| 1995 |  |  | Titular See of Natchitoches | Established | 
| 1995 |  |  | Titular See of Nesqually | Established | 
| 1995 |  |  | Titular See of Quincy | Established | 
| 1995 |  |  | Titular See of Sault Sainte Marie in Michigan | Established | 
| 1995 |  |  | Titular See of Vincennes | Established | 
| 1995 |  |  | Titular See of Concordia | Established | 
| 1996 |  |  | Titular See of California | Established | 
| 1996 |  |  | Titular See of Gardar | Established | 
| 1996 |  |  | Titular See of Oregon City | Established | 
| 1996 | Delegation to Sierra Leone | Elevated | Nunciature to Sierra Leone | Elevated | 
| 1996 | [Patriotic Diocese of Langfang, China] | Territory Added | 
| 1997 |  |  | Patriarchal Dependent Territory of Sudan (Syrian) | Established | 
| 1997 | Patriarchal Exarchate of Jerusalem (Chaldean), Palestine | Elevated | Patriarchal Dependent Territory of Jerusalem (Chaldean), Palestine | Elevated | 
| 1998 | Patriarchal Exarchate of Egypt and Sudan (Melkite Greek) | Elevated | Patriarchal Dependent Territory of Egypt and Sudan (Melkite Greek) | Elevated | 
| 1998 | Patriarchal Exarchate of Jerusalem {Gerusalemme} (Melkite Greek), Palestine | Elevated | Patriarchal Dependent Territory of Jerusalem {Gerusalemme} (Melkite Greek), Palestine | Elevated | 
| 1999 | Delegation to Singapore | Elevated | Nunciature to Singapore | Elevated | 
| 1999 | Pontifical Council for the Interpretation of Legislative Texts, Roman Curia | Name Changed | Pontifical Council for Legislative Texts, Roman Curia | Name Changed | 
| 2002 | Nunciature to Yugoslavia | Split | Nunciature to Serbia and Montenegro | Split | 
| 2004 | Cardinal Titular Church of San Teodoro | Territory Added | 
| 2005 |  |  | Clerical Society of Virgo Flos Carmeli | Founded | 
| 2009 | Nunciature to European Community | Name Changed | Nunciature to European Union | Name Changed | 
| 2009 |  |  | Diocese of Ilorin, Nigeria (from Kaduna) | Metropolitan Changed | 
| 2011 |  |  | Delegation to Viêt Nam | Established | 
| 2012 | Patriarchal Dependent Territory of Egypt and Sudan (Melkite Greek) | Name Changed | Patriarchal Dependent Territory of Egypt, Sudan, and South Sudan (Melkite Greek) | Name Changed | 
| 2012 | Patriarchal Dependent Territory of Sudan (Syrian) | Name Changed | Patriarchal Dependent Territory of Sudan and South Sudan (Syrian) | Name Changed | 
| 2013 | Cardinal Titular Church of San Giovanni Battista Decollato | Territory Added | 
| 2016 | Prefecture for the Economic Affairs of the Holy See, Roman Curia | Territory Added | 
| 2016 |  |  | Diocese of Kingstown, Saint Vincent and Grenadines, Antilles (from Port of Spain) | Metropolitan Changed | 
| 2017 |  |  | Diocese of Gurué, Mozambique (from Beira to Nampula) | Metropolitan Changed | 
| 2018 |  |  | Territorial Prelature of Batanes, Philippines (from Nueva Segovia to Tuguegarao) | Metropolitan Changed | 
| 2019 | Titular See of Valpuesta | Territory Added | 
| 2020 |  |  | Eparchy of Hosur (Syro-Malabar), India (from Immediately Subject) | Metropolitan Changed | 
| 1st Century |  |  | Diocese of Roma {Rome}, Italy | Erected | 
| 1st Century |  |  | Diocese of Brescia, Italy | Erected | 
| 1st Century |  |  | Diocese of Catania, Italy | Erected | 
| 1st Century |  |  | Diocese of Cartagena (en España) | Erected | 
| 1st Century |  |  | Diocese of Cesena, Italy | Erected | 
| 1st Century |  |  | Diocese of Nepi, Italy | Erected | 
| 1st Century |  |  | Diocese of Fano, Italy | Erected | 
| 1st Century |  |  | Diocese of Firenze, Italy | Erected | 
| 1st Century |  |  | Diocese of Fiesole, Italy | Erected | 
| 1st Century |  |  | Diocese of Foligno, Italy | Erected | 
| 1st Century |  |  | Diocese of Guadix, Spain | Erected | 
| 1st Century |  |  | Diocese of Limoges, France | Erected | 
| 1st Century |  |  | Diocese of Lucca, Italy | Erected | 
| 1st Century |  |  | Diocese of Milano, Italy | Erected | 
| 1st Century |  |  | Diocese of Napoli, Italy | Erected | 
| 1st Century |  |  | Diocese of Palermo, Italy | Erected | 
| 1st Century |  |  | Diocese of Pavia, Italy | Erected | 
| 1st Century |  |  | Diocese of Pozzuoli, Italy | Erected | 
| 1st Century |  |  | Diocese of Ravenna, Italy | Erected | 
| 1st Century |  |  | Diocese of Reggio Calabria, Italy | Erected | 
| 1st Century |  |  | Diocese of Reggio Emilia, Italy | Erected | 
| 1st Century |  |  | Diocese of Benevento, Italy | Erected | 
| 1st Century |  |  | Diocese of Spoleto, Italy | Erected | 
| 1st Century |  |  | Diocese of Tarragona, Spain | Erected | 
| 1st Century |  |  | Diocese of Toledo, Spain | Erected | 
| 1st Century |  |  | Diocese of Trier, Germany | Erected | 
| 1st Century |  |  | Diocese of Agrigento (Girgenti), Italy | Erected | 
| 1st Century |  |  | Diocese of Aix, France | Erected | 
| 1st Century |  |  | Diocese of Terracina, Italy | Erected | 
| 1st Century |  |  | Diocese of Marseille, France | Erected | 
| 1st Century |  |  | Diocese of Sens, France | Erected | 
| 1st Century |  |  | Diocese of Malta | Erected | 
| 1st Century |  |  | Diocese of Antiochia {Antioch}, Syria | Erected | 
| 1st Century |  |  | Diocese of Alexandria {Alessandria}, Egypt | Erected | 
| 1st Century |  |  | Diocese of Byzantium, Turkey | Erected | 
| 1st Century |  |  | Archdiocese of Ephesus, Turkey | Erected | 
| 1st Century |  |  | Archdiocese of Hierapolis (Phrygia), Turkey | Erected | 
| 1st Century |  |  | Archdiocese of Edessa (in Osrhoëne), Turkey | Erected | 
| 2nd Century |  |  | Diocese of Avellino, Italy | Erected | 
| 2nd Century |  |  | Diocese of Bayeux, France | Erected | 
| 2nd Century |  |  | Diocese of Belluno, Italy | Erected | 
| 2nd Century |  |  | Diocese of Besançon, France | Erected | 
| 2nd Century |  |  | Diocese of Capua, Italy | Erected | 
| 2nd Century |  |  | Diocese of Forli, Italy | Erected | 
| 2nd Century |  |  | Diocese of Köln, Germany | Erected | 
| 2nd Century |  |  | Diocese of Lyon, France | Erected | 
| 2nd Century |  |  | Diocese of Lugo, Spain | Erected | 
| 2nd Century |  |  | Diocese of Nola, Italy | Erected | 
| 2nd Century |  |  | Diocese of Todi, Italy | Erected | 
| 2nd Century |  |  | Diocese of Perugia, Italy | Erected | 
| 2nd Century |  |  | Diocese of Rouen, France | Erected | 
| 2nd Century |  |  | Diocese of Siracusa, Italy | Erected | 
| 2nd Century |  |  | Diocese of Tivoli, Italy | Erected | 
| 2nd Century |  |  | Diocese of Tortona, Italy | Erected | 
| 2nd Century |  |  | Diocese of Trento, Italy | Erected | 
| 2nd Century |  |  | Diocese of Vicenza, Italy | Erected | 
| 2nd Century |  |  | Diocese of Priverno (or Piperno), Italy | Erected | 
| 3rd Century |  |  | Diocese of Amiens, France | Erected | 
| 3rd Century |  |  | Diocese of Ajaccio, France | Erected | 
| 3rd Century |  |  | Diocese of Angoulême, France | Erected | 
| 3rd Century |  |  | Diocese of Arezzo, Italy | Erected | 
| 3rd Century |  |  | Diocese of Assisi, Italy | Erected | 
| 3rd Century |  |  | Diocese of Asti, Italy | Erected | 
| 3rd Century |  |  | Diocese of Autun, France | Erected | 
| 3rd Century |  |  | Diocese of Bologna, Italy | Erected | 
| 3rd Century |  |  | Archdiocese of Bordeaux, France | Erected | 
| 3rd Century |  |  | Archdiocese of Bourges, France | Erected | 
| 3rd Century |  |  | Diocese of Camerino, Italy | Erected | 
| 3rd Century |  |  | Diocese of Cahors, France | Erected | 
| 3rd Century |  |  | Diocese of Clermont, France | Erected | 
| 3rd Century |  |  | Diocese of Córdoba, Spain | Erected | 
| 3rd Century |  |  | Diocese of Évreux, France | Erected | 
| 3rd Century |  |  | Diocese of Faenza, Italy | Erected | 
| 3rd Century |  |  | Diocese of Fermo, Italy | Erected | 
| 3rd Century |  |  | Suburbicarian See of Frascati, Italy | Erected | 
| 3rd Century |  |  | Diocese of Genova, Italy | Erected | 
| 3rd Century |  |  | Diocese of Ilurir (Eliberi, Elvira, Granada), Spain | Erected | 
| 3rd Century | Diocese of Lyon, France | Elevated | Archdiocese of Lyon, France | Elevated | 
| 3rd Century |  |  | Diocese of Meaux, France | Erected | 
| 3rd Century |  |  | Diocese of Mende, France (or 4th Century) | Erected | 
| 3rd Century |  |  | Diocese of Metz, France | Erected | 
| 3rd Century |  |  | Diocese of Chiusi, Italy | Erected | 
| 3rd Century |  |  | Diocese of Maguelonne, France | Erected | 
| 3rd Century |  |  | Diocese of Nice, France | Erected | 
| 3rd Century |  |  | Diocese of Nocera de’ Pagani, Italy (or 4th Century) | Erected | 
| 3rd Century |  |  | Diocese of Orléans, France | Erected | 
| 3rd Century |  |  | Suburbicarian See of Ostia, Italy | Erected | 
| 3rd Century |  |  | Diocese of Padova {Padua}, Italy | Erected | 
| 3rd Century |  |  | Diocese of Palencia, Spain | Erected | 
| 3rd Century |  |  | Diocese of Paris, France | Erected | 
| 3rd Century |  |  | Diocese of Pesaro, Italy | Erected | 
| 3rd Century |  |  | Diocese of Pistoia, Italy | Erected | 
| 3rd Century |  |  | Diocese of Poitiers, France | Erected | 
| 3rd Century |  |  | Diocese of Poreč (Parenzo), Croatia | Erected | 
| 3rd Century |  |  | Diocese of Porto, Italy | Erected | 
| 3rd Century |  |  | Diocese of Rennes, France | Erected | 
| 3rd Century |  |  | Diocese of Rimini, Italy | Erected | 
| 3rd Century |  |  | Diocese of Sevilla, Spain | Erected | 
| 3rd Century |  |  | Diocese of Sées {Séez}, France | Erected | 
| 3rd Century |  |  | Diocese of Soissons, France | Erected | 
| 3rd Century |  |  | Diocese of Sora, Italy | Erected | 
| 3rd Century |  |  | Diocese of Salona, Croatia | Erected | 
| 3rd Century |  |  | Diocese of Toulouse, France | Erected | 
| 3rd Century |  |  | Diocese of Tours, France | Erected | 
| 3rd Century |  |  | Diocese of Vercelli, Italy | Erected | 
| 3rd Century |  |  | Diocese of Verona, Italy | Erected | 
| 3rd Century |  |  | Diocese of Ancona, Italy | Erected | 
| 3rd Century |  |  | Diocese of Toscanella (Tuscania), Italy | Erected | 
| 3rd Century |  |  | Diocese of Modena, Italy | Erected | 
| 3rd Century |  |  | Diocese of Siponto, Italy | Erected | 
| 3rd Century |  |  | Archeparchy of Damas (Melkite Greek), Syria | Erected | 
| 3rd Century |  |  | Cardinal Titular Church of Frascati | Erected | 
| 3rd Century |  |  | Cardinal Titular Church of Porto | Erected | 
| 3rd Century |  |  | Diocese of Albi, France | Erected | 
| 3rd Century |  |  | Diocese of Arles, France | Erected | 
| 3rd Century |  |  | Diocese of Auxerre, France | Erected | 
| 3rd Century |  |  | Diocese of Beauvais, France | Erected | 
| 3rd Century |  |  | Diocese of Chartres, France | Erected | 
| 3rd Century |  |  | Diocese of Die, France | Erected | 
| 3rd Century |  |  | Diocese of Langres, France | Erected | 
| 3rd Century |  |  | Diocese of Le Puy-en-Velay, France | Erected | 
| 3rd Century |  |  | Diocese of Narbonne, France | Erected | 
| 3rd Century |  |  | Diocese of Périgueux (Vesuna), France | Erected | 
| 3rd Century |  |  | Diocese of Reims, France | Erected | 
| 3rd Century |  |  | Diocese of Saintes, France | Erected | 
| 3rd Century | Diocese of Sens, France | Elevated | Archdiocese of Sens, France | Elevated | 
| 3rd Century |  |  | Diocese of Vienne, France | Erected | 
| 3rd Century |  |  | Diocese of Petelia, Italy | Erected | 
| 3rd Century |  |  | Cardinal Titular Church of Ostia | Erected | 
| 3rd Century |  |  | Diocese of Tarsus, Turkey | Erected | 
| 4th Century |  |  | Diocese of Agen, France | Erected | 
| 4th Century |  |  | Diocese of Alba (Pompea), Italy | Erected | 
| 4th Century |  |  | Diocese of Acqui, Italy | Erected | 
| 4th Century |  |  | Diocese of Ávila, Spain | Erected | 
| 4th Century |  |  | Diocese of Ascoli Piceno, Italy | Erected | 
| 4th Century |  |  | Diocese of Barcelona, Spain | Erected | 
| 4th Century |  |  | Diocese of Bari, Italy | Erected | 
| 4th Century |  |  | Diocese of Bayonne, France ((or 6th Century)) | Erected | 
| 4th Century | Diocese of Besançon, France | Elevated | Archdiocese of Besançon, France | Elevated | 
| 4th Century |  |  | Diocese of Bergamo, Italy | Erected | 
| 4th Century |  |  | Diocese of Braga, Portugal | Erected | 
| 4th Century |  |  | Diocese of Brindisi, Italy | Erected | 
| 4th Century |  |  | Diocese of Cagliari, Italy | Erected | 
| 4th Century |  |  | Diocese of Squillace, Italy | Erected | 
| 4th Century |  |  | Diocese of Sarsina, Italy | Erected | 
| 4th Century |  |  | Diocese of Concordia (Sagittaria), Italy | Erected | 
| 4th Century |  |  | Diocese of Como, Italy | Erected | 
| 4th Century |  |  | Diocese of Cremona, Italy | Erected | 
| 4th Century |  |  | Diocese of Cagli, Italy | Erected | 
| 4th Century |  |  | Diocese of Digne, France | Erected | 
| 4th Century |  |  | Diocese of Évora, Portugal | Erected | 
| 4th Century |  |  | Diocese of Ferentino, Italy | Erected | 
| 4th Century |  |  | Diocese of Gerona, Spain | Erected | 
| 4th Century |  |  | Diocese of Piacenza, Italy | Erected | 
| 4th Century |  |  | Diocese of Grenoble, France | Erected | 
| 4th Century |  |  | Diocese of Imola, Italy | Erected | 
| 4th Century |  |  | Diocese of Genève {Geneva}, Switzerland | Erected | 
| 4th Century |  |  | Diocese of León, Spain | Erected | 
| 4th Century |  |  | Diocese of Lisboa, Portugal | Erected | 
| 4th Century |  |  | Diocese of Lodi, Italy | Erected | 
| 4th Century |  |  | Diocese of Lucera, Italy | Erected | 
| 4th Century |  |  | Diocese of Mainz, Germany | Erected | 
| 4th Century | Diocese of Milano, Italy | Elevated | Archdiocese of Milano {Milan}, Italy | Elevated | 
| 4th Century |  |  | Diocese of Nantes, France | Erected | 
| 4th Century |  |  | Diocese of Novara, Italy | Erected | 
| 4th Century |  |  | Suburbicarian See of Palestrina, Italy | Erected | 
| 4th Century |  |  | Diocese of Parma, Italy | Erected | 
| 4th Century |  |  | Diocese of Pisa, Italy | Erected | 
| 4th Century |  |  | Diocese of Porto, Portugal | Erected | 
| 4th Century | Diocese of Sevilla, Spain | Elevated | Archdiocese of Sevilla {Seville}, Spain | Elevated | 
| 4th Century |  |  | Suburbicarian See of Albano, Italy | Erected | 
| 4th Century |  |  | Archdiocese of Dardania, North Macedonia | Erected | 
| 4th Century |  |  | Diocese of Siena, Italy | Erected | 
| 4th Century |  |  | Diocese of Sion {Sitten}, Switzerland | Erected | 
| 4th Century |  |  | Diocese of Castellammare di Stabia, Italy | Erected | 
| 4th Century |  |  | Diocese of Speyer, Germany | Erected | 
| 4th Century |  |  | Diocese of Strasbourg, France | Erected | 
| 4th Century |  |  | Diocese of Narni, Italy | Erected | 
| 4th Century |  |  | Diocese of Civita (Tempio), Italy | Erected | 
| 4th Century | Diocese of Toledo, Spain | Elevated | Archdiocese of Toledo, Spain | Elevated | 
| 4th Century |  |  | Diocese of Torino, Italy | Erected | 
| 4th Century |  |  | Diocese of Tortosa, Spain | Erected | 
| 4th Century |  |  | Diocese of Treviso, Italy | Erected | 
| 4th Century |  |  | Diocese of Troyes, France | Erected | 
| 4th Century |  |  | Diocese of Urgell, Spain | Erected | 
| 4th Century |  |  | Diocese of Valence, France | Erected | 
| 4th Century |  |  | Diocese of Acerenza, Italy | Erected | 
| 4th Century |  |  | Eparchy of Alep (Melkite Greek), Syria | Erected | 
| 4th Century |  |  | Diocese of Avignon, France | Erected | 
| 4th Century |  |  | Diocese of Sirmio (Srijem; Sirmium), Croatia | Erected | 
| 4th Century |  |  | Confederation of Canons Regular of St. Augustine | Founded | 
| 4th Century |  |  | Cardinal Titular Church of Albano | Erected | 
| 4th Century |  |  | Cardinal Titular Church of Palestrina | Erected | 
| 4th Century |  |  | Cardinal Titular Church of Santa Cecilia | Established | 
| 4th Century |  |  | Diocese of Antibes, France | Erected | 
| 4th Century |  |  | Diocese of Apt, France | Erected | 
| 4th Century |  |  | Diocese of Chalons-sur-Marne, France | Erected | 
| 4th Century |  |  | Diocese of Cimiez, France | Erected | 
| 4th Century |  |  | Diocese of (Saint-Lizier de) Couserans (or Conserans), France | Erected | 
| 4th Century |  |  | Diocese of Embrun, France | Erected | 
| 4th Century |  |  | Diocese of Fréjus, France | Erected | 
| 4th Century |  |  | Diocese of Lectoure, France | Erected | 
| 4th Century |  |  | Diocese of Nevers, France | Erected | 
| 4th Century | Diocese of Reims, France | Elevated | Archdiocese of Reims, France | Elevated | 
| 4th Century |  |  | Diocese of Saint-Paul-Trois-Châteaux, France | Erected | 
| 4th Century |  |  | Diocese of Tarbes, France | Erected | 
| 4th Century |  |  | Diocese of Verdun, France | Erected | 
| 4th Century |  |  | Diocese of Vernay, France | Erected | 
| 4th Century |  |  | Diocese of Viviers (Aps), France | Erected | 
| 4th Century |  |  | Diocese of Aosta, Italy | Erected | 
| 4th Century |  |  | Diocese of London, England, Great Britain | Erected | 
| 4th Century |  |  | Archeparchy of Beirut {Bairut} (Melkite Greek), Lebanon | Erected | 
| 4th Century |  |  | Diocese of Amiterno, Italy | Erected | 
| 4th Century |  |  | Diocese of Atella, Italy | Erected | 
| 4th Century |  |  | Diocese of Eca, Italy | Erected | 
| 4th Century |  |  | Diocese of Helvetii / Aventicum [Avenches] / Vindonissa [Windisch], Switzerland | Erected | 
| 4th Century |  |  | Diocese of Ancyra (Phrygia), Turkey | Erected | 
| 4th Century |  |  | Apostolic Chancery, Roman Curia | Established | 
| 4th Century |  |  | Diocese of Canosa (di Puglia), Italy | Erected | 
| 5th Century |  |  | Diocese of Connor, Ireland | Erected | 
| 5th Century |  |  | Diocese of Killaloe, Ireland | Erected | 
| 5th Century |  |  | Diocese of Kilmore, Ireland | Erected | 
| 5th Century |  |  | Diocese of Raphoe, Ireland | Erected | 
| 5th Century |  |  | Diocese of Alife, Italy | Erected | 
| 5th Century |  |  | Diocese of Bosa, Italy | Erected | 
| 5th Century |  |  | Diocese of Ardagh (and Clonmacnois), Ireland | Erected | 
| 5th Century |  |  | Diocese of Gualdo Tadino, Italy | Erected | 
| 5th Century |  |  | Diocese of Nocera Umbra, Italy | Erected | 
| 5th Century |  |  | Diocese of Calahorra, Spain | Erected | 
| 5th Century |  |  | Diocese of Cassano all’Jonio, Italy | Erected | 
| 5th Century |  |  | Diocese of Telese o Cerreto Sannita, Italy | Erected | 
| 5th Century |  |  | Diocese of Chur, Switzerland | Erected | 
| 5th Century |  |  | Diocese of Sutri, Italy | Erected | 
| 5th Century |  |  | Diocese of Conversano, Italy | Erected | 
| 5th Century |  |  | Diocese of Coutances, France | Erected | 
| 5th Century |  |  | Diocese of Fossombrone, Italy | Erected | 
| 5th Century |  |  | Diocese of Bovino, Italy | Erected | 
| 5th Century |  |  | Diocese of Gubbio, Italy | Erected | 
| 5th Century |  |  | Diocese of Isernia, Italy | Erected | 
| 5th Century |  |  | Diocese of Le Mans, France | Erected | 
| 5th Century |  |  | Diocese of Gerace, Italy | Erected | 
| 5th Century |  |  | Diocese of Lérida, Spain | Erected | 
| 5th Century |  |  | Diocese of Cingoli, Italy | Erected | 
| 5th Century |  |  | Diocese of Tolentino, Italy | Erected | 
| 5th Century |  |  | Diocese of Mallorca, Spain | Erected | 
| 5th Century |  |  | Diocese of Massa Marittima, Italy | Erected | 
| 5th Century |  |  | Diocese of Venosa, Italy | Erected | 
| 5th Century |  |  | Diocese of Menorca, Spain | Erected | 
| 5th Century |  |  | Diocese of Messina, Italy | Erected | 
| 5th Century |  |  | Diocese of Orense, Spain | Erected | 
| 5th Century |  |  | Diocese of Pamplona, Spain | Erected | 
| 5th Century |  |  | Diocese of Tarazona, Spain | Erected | 
| 5th Century |  |  | Diocese of Penne, Italy | Erected | 
| 5th Century |  |  | Diocese of Teramo, Italy | Erected | 
| 5th Century |  |  | Diocese of Potenza, Italy | Erected | 
| 5th Century |  |  | Diocese of Quimper, France | Erected | 
| 5th Century | Diocese of Ravenna, Italy | Elevated | Archdiocese of Ravenna, Italy | Elevated | 
| 5th Century |  |  | Diocese of Rieti, Italy | Erected | 
| 5th Century | Diocese of Rouen, France | Elevated | Archdiocese of Rouen, France (or 6th Century) | Elevated | 
| 5th Century |  |  | Diocese of Forum Novum, Italy | Erected | 
| 5th Century |  |  | Diocese of Saint-Brieuc, France | Erected | 
| 5th Century |  |  | Diocese of Torres, Italy | Erected | 
| 5th Century |  |  | Diocese of Aquino, Italy | Erected | 
| 5th Century |  |  | Diocese of Norcia, Italy | Erected | 
| 5th Century |  |  | Diocese of Sorrento, Italy | Erected | 
| 5th Century | Diocese of Salona, Croatia | Elevated | Archdiocese of Salona, Croatia | Elevated | 
| 5th Century |  |  | Diocese of Valva, Italy | Erected | 
| 5th Century |  |  | Diocese of Calvi Risorta, Italy | Erected | 
| 5th Century | Diocese of Tarragona, Spain | Elevated | Archdiocese of Tarragona, Spain | Elevated | 
| 5th Century |  |  | Diocese of Amelia, Italy | Erected | 
| 5th Century |  |  | Diocese of Larino, Italy | Erected | 
| 5th Century | Diocese of Tours, France | Elevated | Archdiocese of Tours, France | Elevated | 
| 5th Century |  |  | Diocese of Segni, Italy | Erected | 
| 5th Century |  |  | Diocese of Velletri, Italy | Erected | 
| 5th Century |  |  | Diocese of Vannes, France | Erected | 
| 5th Century |  |  | Diocese of Vic, Spain | Erected | 
| 5th Century |  |  | Diocese of Volterra, Italy | Erected | 
| 5th Century |  |  | Diocese of Zaragoza, Spain | Erected | 
| 5th Century |  |  | Diocese of Ivrea, Italy | Erected | 
| 5th Century | Diocese of Aix, France | Elevated | Archdiocese of Aix, France | Elevated | 
| 5th Century |  |  | Diocese of Albenga, Italy | Erected | 
| 5th Century |  |  | Diocese of Anagni, Italy | Erected | 
| 5th Century |  |  | Diocese of Sessa Aurunca, Italy | Erected | 
| 5th Century |  |  | Diocese of Matelica, Italy | Erected | 
| 5th Century |  |  | Archeparchy of Perat-Maishan (Chaldean), Iraq | Erected | 
| 5th Century |  |  | Cardinal Titular Church of Santi Giovanni e Paolo | Established | 
| 5th Century |  |  | Diocese of Acqs (Dax), France | Erected | 
| 5th Century |  |  | Diocese of Agde, France | Erected | 
| 5th Century |  |  | Diocese of Aire, France | Erected | 
| 5th Century |  |  | Diocese of Belley, France | Erected | 
| 5th Century |  |  | Diocese of (Saint-Bertrand de) Comminges, France | Erected | 
| 5th Century |  |  | Diocese of Gap, France | Erected | 
| 5th Century |  |  | Diocese of Laon, France | Erected | 
| 5th Century |  |  | Diocese of Mariana, France | Erected | 
| 5th Century |  |  | Diocese of Nebbio, France | Erected | 
| 5th Century |  |  | Diocese of Nîmes, France | Erected | 
| 5th Century |  |  | Diocese of Rodez, France | Erected | 
| 5th Century |  |  | Diocese of Tarentaise (Moûtiers-en-Tarentaise), France | Erected | 
| 5th Century |  |  | Diocese of Vence, France | Erected | 
| 5th Century |  |  | Cardinal Titular Church of San Vitale | Established | 
| 5th Century |  |  | Cardinal Titular Church of Sabina | Erected | 
| 5th Century |  |  | Diocese of Literno, Italy | Erected | 
| 5th Century |  |  | Diocese of Iria Flavia (Iria, Locus Sancti Iacobi), Spain (or 6th Century) | Erected | 
| 6th Century |  |  | Diocese of Augsburg, Germany | Erected | 
| 6th Century | Diocese of Bari, Italy Diocese of Canosa (di Puglia), Italy
 | Elevated | Archdiocese of Bari (-Canosa), Italy | Elevated | 
| 6th Century |  |  | Diocese of Arras, France | Erected | 
| 6th Century |  |  | Diocese of Kerry (o Ardfert) e Aghadoe, Ireland | Erected | 
| 6th Century |  |  | Diocese of Down, Ireland | Erected | 
| 6th Century |  |  | Diocese of Ruvo (Ruo)(di Puglia), Italy | Erected | 
| 6th Century |  |  | Diocese of Killala, Ireland | Erected | 
| 6th Century |  |  | Diocese of Feltre, Italy | Erected | 
| 6th Century |  |  | Diocese of Sabiona-Säben, Italy | Erected | 
| 6th Century |  |  | Diocese of Cambrai, France | Erected | 
| 6th Century |  |  | Diocese of Chieti, Italy | Erected | 
| 6th Century |  |  | Diocese of Coimbra, Portugal | Erected | 
| 6th Century |  |  | Diocese of Crotone (Cotrone), Italy | Erected | 
| 6th Century |  |  | Diocese of Comacchio, Italy | Erected | 
| 6th Century |  |  | Diocese of Guarda, Portugal | Erected | 
| 6th Century |  |  | Diocese of Jesi, Italy | Erected | 
| 6th Century |  |  | Diocese of Nicastro, Italy | Erected | 
| 6th Century | Diocese of Helvetii / Aventicum [Avenches] / Vindonissa [Windisch], Switzerland | Territory Lost | Diocese of Konstanz {Constance}, Germany Diocese of Lausanne, Switzerland
 | Erected | 
| 6th Century |  |  | Diocese of Nicotera, Italy | Erected | 
| 6th Century |  |  | Diocese of Gallipoli, Italy | Erected | 
| 6th Century |  |  | Diocese of Amalfi, Italy | Erected | 
| 6th Century |  |  | Diocese of Orvieto, Italy | Erected | 
| 6th Century |  |  | Diocese of Pula (Pola), Croatia | Erected | 
| 6th Century |  |  | Diocese of Santa Rufina, Italy | Erected | 
| 6th Century |  |  | Diocese of Cervia, Italy | Erected | 
| 6th Century |  |  | Diocese of Salerno, Italy | Erected | 
| 6th Century |  |  | Diocese of Salzburg, Austria | Erected | 
| 6th Century |  |  | Diocese of Segorbe, Spain | Erected | 
| 6th Century |  |  | Diocese of Segovia, Spain | Erected | 
| 6th Century | Diocese of Ostra, Italy | Territory Lost | Diocese of Senigallia, Italy | Erected | 
| 6th Century |  |  | Diocese of Makarska, Croatia | Erected | 
| 6th Century |  |  | Diocese of Sulmona, Italy | Erected | 
| 6th Century |  |  | Diocese of Taranto, Italy | Erected | 
| 6th Century |  |  | Diocese of Teano, Italy | Erected | 
| 6th Century |  |  | Diocese of Tournai, Belgium | Erected | 
| 6th Century |  |  | Diocese of Trani, Italy | Erected | 
| 6th Century |  |  | Diocese of Trieste, Italy | Erected | 
| 6th Century |  |  | Diocese of Tude (Tuy), Spain | Erected | 
| 6th Century |  |  | Diocese of Urbino, Italy | Erected | 
| 6th Century |  |  | Diocese of Ceneda, Italy | Erected | 
| 6th Century |  |  | Territorial Abbey of Montecassino, Italy | Erected | 
| 6th Century |  |  | Diocese of Alatri, Italy | Erected | 
| 6th Century |  |  | Diocese of Lescar, France | Erected | 
| 6th Century |  |  | Diocese of Oloron (Oloron-Sainte-Marie), France | Erected | 
| 6th Century |  |  | Diocese of Bagnoregio (Bagnorea), Italy | Erected | 
| 6th Century |  |  | Diocese of Viterbo, Italy | Erected | 
| 6th Century | Eparchy of Alep (Melkite Greek), Syria | Elevated | Archeparchy of Alep [Beroea, Halab] (Melkite Greek), Syria | Elevated | 
| 6th Century |  |  | Order of Saint Benedict | Founded | 
| 6th Century |  |  | Diocese of Aleria, France | Erected | 
| 6th Century |  |  | Diocese of Auch, France | Erected | 
| 6th Century |  |  | Diocese of Elne, France | Erected | 
| 6th Century |  |  | Diocese of Saint-Jean-de-Maurienne, France | Erected | 
| 6th Century |  |  | Diocese of Saint-Pol-de-Léon, France | Erected | 
| 6th Century |  |  | Diocese of Saint David’s, Wales, Great Britain | Erected | 
| 6th Century |  |  | Diocese of Asolo (Cittanova; Eraclea), Italy | Erected | 
| 6th Century |  |  | Diocese of Aleth, France | Erected | 
| 6th Century | Diocese of Tarsus, Turkey | Elevated | Archdiocese of Tarsus, Turkey | Elevated | 
| 7th Century |  |  | Diocese of Ferns, Ireland | Erected | 
| 7th Century |  |  | Diocese of Cork, Ireland | Erected | 
| 7th Century |  |  | Diocese of Limerick, Ireland | Erected | 
| 7th Century |  |  | Diocese of Chioggia, Italy | Erected | 
| 7th Century |  |  | Diocese of Città di Castello, Italy | Erected | 
| 7th Century |  |  | Diocese of Orte, Italy | Erected | 
| 7th Century |  |  | Diocese of Bisignano, Italy (or 8th Century) | Erected | 
| 7th Century |  |  | Diocese of Cosenza, Italy | Erected | 
| 7th Century |  |  | Diocese of Santa Severina, Italy | Erected | 
| 7th Century |  |  | Diocese of Jaén, Spain | Erected | 
| 7th Century |  |  | Diocese of Osimo, Italy | Erected | 
| 7th Century |  |  | Diocese of Tropea, Italy | Erected | 
| 7th Century |  |  | Diocese of Otranto, Italy | Erected | 
| 7th Century |  |  | Diocese of Sovana (Soana), Italy | Erected | 
| 7th Century |  |  | Diocese of Bova, Italy | Erected | 
| 7th Century |  |  | Diocese of Rossano, Italy | Erected | 
| 7th Century |  |  | Diocese of Ventimiglia, Italy | Erected | 
| 7th Century |  |  | Diocese of Vrhbosna, Bosnia and Herzegovina | Erected | 
| 7th Century |  |  | Diocese of Adria, Italy | Erected | 
| 7th Century |  |  | Diocese of Ales (Uselli), Italy | Erected | 
| 7th Century |  |  | Diocese of Polignano (Polinianum), Italy | Erected | 
| 7th Century |  |  | Diocese of Vico Equense, Italy | Erected | 
| 7th Century |  |  | Diocese of Thérouanne, France | Erected | 
| 7th Century |  |  | Diocese of Selsey, England, Great Britain | Erected | 
| 7th Century |  |  | Diocese of Winchester, England, Great Britain | Erected | 
| 7th Century |  |  | Diocese of Bisarcio, Italy | Erected | 
| 7th Century | Archdiocese of Edessa (in Osrhoëne), Turkey | Territory Added | 
| 8th Century |  |  | Diocese of Gallese, Italy | Erected | 
| 8th Century |  |  | Diocese of Veroli, Italy | Erected | 
| 8th Century | Diocese of Köln, Germany | Elevated | Archdiocese of Köln {Cologne}, Germany | Elevated | 
| 8th Century |  |  | Diocese of Conza, Italy | Erected | 
| 8th Century |  |  | Diocese of Bisceglie, Italy | Erected | 
| 8th Century | Diocese of Trier, Germany | Elevated | Archdiocese of Trier, Germany | Elevated | 
| 8th Century |  |  | Diocese of Sezze, Italy | Erected | 
| 9th Century |  |  | Diocese of Caiazzo, Italy | Erected | 
| 9th Century |  |  | Diocese of Bar, Montenegro | Erected | 
| 9th Century |  |  | Diocese of Marsi, Italy | Erected | 
| 9th Century |  |  | Diocese of Bitonto, Italy | Erected | 
| 9th Century |  |  | Diocese of Beograd {Belgrade}, Serbia | Erected | 
| 9th Century |  |  | Diocese of Tinos, Greece | Erected | 
| 9th Century |  |  | Diocese of Pult (Pulati), Albania | Erected | 
| 9th Century |  |  | Diocese of Montefeltro, Italy | Erected | 
| 9th Century |  |  | Diocese of Gravina (di Puglia), Italy | Erected | 
| 9th Century |  |  | Diocese of Matera, Italy | Erected | 
| 9th Century |  |  | Diocese of Minervino Murge, Italy | Erected | 
| 9th Century |  |  | Diocese of Equilio (Jesolo), Italy | Erected | 
| 9th Century |  |  | Diocese of Novigrad (Cittanova), Croatia | Erected | 
| 9th Century |  |  | Diocese of Konavlje, Albania | Erected | 
| 9th Century | Diocese of Formia, Italy | Name Changed | Diocese of Formia-Gaeta (Caieta), Italy | Name Changed | 
| 9th Century |  |  | Diocese of Capodistria (Capo d’Istria)(Koper), Slovenia | Erected | 
| 10th Century | Diocese of Sabiona-Säben, Italy | Name Changed | Diocese of Brixen {Bressanone}, Italy | Name Changed | 
| 10th Century | Diocese of Brindisi, Italy | Elevated | Archdiocese of Brindisi, Italy | Elevated | 
| 10th Century |  |  | Diocese of Cashel, Ireland | Erected | 
| 10th Century |  |  | Diocese of Eger, Hungary | Erected | 
| 10th Century | Diocese of Nitra, Slovakia Diocese of Passau, Germany
 Diocese of Regensburg, Germany
 | Territory Lost | Archdiocese of Esztergom, Hungary | Erected | 
| 10th Century |  |  | Diocese of Kotor (Cattaro), Montenegro | Erected | 
| 10th Century | Diocese of Napoli, Italy | Elevated | Archdiocese of Napoli {Naples}, Italy | Elevated | 
| 10th Century |  |  | Diocese of Płock, Poland | Erected | 
| 10th Century | Diocese of Salerno, Italy | Elevated | Archdiocese of Salerno, Italy | Elevated | 
| 10th Century |  |  | Diocese of Salamanca, Spain | Restored | 
| 10th Century |  |  | Diocese of Savona, Italy | Erected | 
| 10th Century |  |  | Diocese of Prizren, Serbia | Erected | 
| 10th Century | Diocese of Taranto, Italy | Elevated | Archdiocese of Taranto, Italy | Elevated | 
| 10th Century |  |  | Diocese of Termoli, Italy | Erected | 
| 10th Century |  |  | Diocese of Trivento, Italy | Erected | 
| 10th Century |  |  | Diocese of Zamora, Spain | Erected | 
| 10th Century |  |  | Diocese of Trebinje, Bosnia and Herzegovina | Erected | 
| 10th Century |  |  | Diocese of Leuca, Italy | Erected | 
| 10th Century |  |  | Diocese of Amantea, Italy | Erected | 
| 10th Century | Diocese of Egara, Spain | Suppressed | Diocese of Barcelona, Spain | Territory Added | 
| 11th Century |  |  | Diocese of Acerra, Italy | Erected | 
| 11th Century |  |  | Diocese of Ariano, Italy | Erected | 
| 11th Century |  |  | Diocese of Lacedonia, Italy | Erected | 
| 11th Century |  |  | Diocese of Ávila, Spain | Restored | 
| 11th Century |  |  | Diocese of Ostuni, Italy | Erected | 
| 11th Century | Diocese of Cagliari, Italy | Elevated | Archdiocese of Cagliari, Italy | Elevated | 
| 11th Century |  |  | Diocese of Boiano, Italy | Erected | 
| 11th Century |  |  | Diocese of Castellaneta, Italy | Erected | 
| 11th Century |  |  | Diocese of Ascoli Satriano (Puglia), Italy | Erected | 
| 11th Century |  |  | Diocese of Monopoli, Italy | Erected | 
| 11th Century | Diocese of Santa Severina, Italy | Elevated | Archdiocese of Santa Severina, Italy | Elevated | 
| 11th Century |  |  | Diocese of Bobbio, Italy | Erected | 
| 11th Century |  |  | Diocese of Győr (Raab), Hungary | Erected | 
| 11th Century |  |  | Diocese of Venafro, Italy | Erected | 
| 11th Century |  |  | Diocese of Melfi, Italy | Erected | 
| 11th Century |  |  | Diocese of Rapolla, Italy | Erected | 
| 11th Century |  |  | Diocese of Giovinazzo, Italy | Erected | 
| 11th Century |  |  | Diocese of Terlizzi, Italy | Erected | 
| 11th Century |  |  | Diocese of Sarno, Italy | Erected | 
| 11th Century | Diocese of Otranto, Italy | Elevated | Archdiocese of Otranto, Italy | Elevated | 
| 11th Century | Diocese of Palermo, Italy | Elevated | Archdiocese of Palermo, Italy | Elevated | 
| 11th Century |  |  | Diocese of Muro Lucano, Italy | Erected | 
| 11th Century | Diocese of Reggio Calabria, Italy | Elevated | Archdiocese of Reggio Calabria, Italy | Elevated | 
| 11th Century |  |  | Diocese of Acerno, Italy | Erected | 
| 11th Century | Diocese of Conza, Italy | Elevated | Archdiocese of Conza, Italy | Elevated | 
| 11th Century |  |  | Diocese of Nusco, Italy | Erected | 
| 11th Century |  |  | Diocese of Civitate (Città or Civita), Italy | Erected | 
| 11th Century |  |  | Diocese of Anglona, Italy | Erected | 
| 11th Century | Diocese of Trani, Italy | Elevated | Archdiocese of Trani, Italy | Elevated | 
| 11th Century |  |  | Diocese of Tricarico, Italy | Erected | 
| 11th Century |  |  | Diocese of Vác, Hungary | Erected | 
| 11th Century |  |  | Territorial Abbey of Subiaco, Italy | Erected | 
| 11th Century | Diocese of Acerenza, Italy | Elevated | Archdiocese of Acerenza, Italy | Elevated | 
| 11th Century |  |  | Diocese of Andria, Italy | Erected | 
| 11th Century | Diocese of Matera, Italy | Elevated | Archdiocese of Matera, Italy | Elevated | 
| 11th Century |  |  | Diocese of Bosnia (Bosna, Diacovar, Diakovar), Croatia | Erected | 
| 11th Century |  |  | Apostolic Chamber, Roman Curia | Established | 
| 11th Century |  |  | Diocese of Korčula (Curzola, Cursola), Croatia | Erected | 
| 11th Century |  |  | Diocese of Stagno (Ston), Croatia | Erected | 
| 11th Century |  |  | Diocese of Sorres (Sorra), Italy | Erected | 
| 11th Century |  |  | Canons Regular of the Hospitaller Congregation of Great Saint Bernard | Founded | 
| 11th Century |  |  | Canons Regular of the Lateran Congregation of Austria | Founded | 
| 11th Century |  |  | Diocese of Suelli, Italy | Erected | 
| 11th Century | Diocese of Bomarzo, Italy | Suppressed | Diocese of Bagnoregio (Bagnorea), Italy | Territory Added | 
| 11th Century | Diocese of Grumento Nova (Grumentum), Italy | Name Changed | Diocese of Marsico Nuovo, Italy | Name Changed | 
| 12th Century | Diocese of Roda, Spain | Name Changed | Diocese of Barbastro, Spain | Name Changed | 
| 12th Century |  |  | Diocese of Caserta, Italy | Erected | 
| 12th Century |  |  | Diocese of Hvar (Lesina), Croatia | Erected | 
| 12th Century |  |  | Diocese of Lamego, Portugal | Erected | 
| 12th Century | Diocese of Messina, Italy | Elevated | Archdiocese of Messina, Italy | Elevated | 
| 12th Century |  |  | Diocese of Molfetta, Italy | Erected | 
| 12th Century |  |  | Diocese of Galtelli, Italy | Erected | 
| 12th Century |  |  | Diocese of Osma, Spain | Erected | 
| 12th Century |  |  | Diocese of Bisaccia, Italy | Erected | 
| 12th Century |  |  | Diocese of Sant’Angelo dei Lombardi, Italy | Erected | 
| 12th Century |  |  | Diocese of Ampurias, Italy | Erected | 
| 12th Century |  |  | Territorial Abbey of Montevergine, Italy | Erected | 
| 12th Century |  |  | Diocese of Terralba, Italy | Erected | 
| 12th Century | Diocese of Viterbo, Italy | United | 
| 12th Century |  |  | Apostolic Penitentiary, Roman Curia | Established | 
| 12th Century | Diocese of Skara, Sweden | Territory Lost | Diocese of Linköping, Sweden | Erected | 
| 12th Century |  |  | Diocese of Västerås (Westeraes), Sweden | Erected | 
| 12th Century |  |  | Diocese of Caithness, Scotland, Great Britain | Erected | 
| 12th Century |  |  | Diocese of Dunblane, Scotland, Great Britain | Erected | 
| 12th Century |  |  | Diocese of Dunkeld, Scotland, Great Britain | Erected | 
| 12th Century |  |  | Diocese of Ross (Rosemarkie, Fortrose), Scotland, Great Britain | Erected | 
| 12th Century |  |  | Diocese of Scardona (Skradin), Croatia | Erected | 
| 12th Century |  |  | Diocese of Trogir (Traù), Croatia | Erected | 
| 12th Century | Diocese of Forum Novum, Italy | Name Changed | Diocese of Vescovio, Italy | Name Changed | 
| 12th Century | Diocese of Ancyra (Phrygia), Turkey | Territory Added | 
| 12th Century |  |  | Diocese of Albania | Erected | 
| 13th Century |  |  | Diocese of La Calzada, Spain | Erected | 
| 13th Century | Diocese of Calahorra, Spain Diocese of La Calzada, Spain
 | United | Diocese of Calahorra y La Calzada, Spain | United | 
| 13th Century |  |  | Diocese of Chios (Scio), Greece | Erected | 
| 13th Century |  |  | Diocese of Cefalonia, Greece | Erected | 
| 13th Century |  |  | Diocese of Naxos, Greece | Erected | 
| 13th Century |  |  | Diocese of Oppido Mamertina, Italy | Erected | 
| 13th Century |  |  | Diocese of Syros (e Milos), Greece | Erected | 
| 13th Century |  |  | Diocese of Ugento, Italy | Erected | 
| 13th Century |  |  | Diocese of Warmia (Ermland), Poland | Erected | 
| 13th Century |  |  | Territorial Abbey of San Martino al Monte Cimino, Italy | Erected | 
| 13th Century |  |  | Archdiocese of Durrës (Durazzo), Albania | Erected | 
| 13th Century |  |  | Order of Friars Preachers | Founded | 
| 13th Century |  |  | Diocese of Andros, Greece | Erected | 
| 13th Century |  |  | Diocese of Budua (Budva), Montenegro | Erected | 
| 13th Century | Diocese of Sulmona, Italy Diocese of Valva, Italy
 | United | Diocese of Valva e Sulmona, Italy | United | 
| 13th Century | Diocese of Leuca, Italy | Name Changed | Diocese of Alessano, Italy | Name Changed | 
| 13th Century | Archdiocese of Tarsus, Turkey | Territory Added | 
| 13th Century |  |  | Diocese of Galtelli, Italy (from Pisa) | Metropolitan Changed | 
| 14th Century |  |  | Diocese of Lezhë {Lesh, Alessio}, Albania | Erected | 
| 14th Century |  |  | Diocese of Cariati, Italy | Erected | 
| 14th Century |  |  | Diocese of Vilnius, Lithuania | Erected | 
| 14th Century |  |  | Orden de San Jerónimo | Founded | 
| 14th Century |  |  | Canons Regular of the Congregation of the Brothers of Community Life | Founded | 
| 14th Century |  |  | Diocese of Kisamos (Cisamo), Greece | Erected | 
| 14th Century | Archdiocese of Hierapolis (Phrygia), Turkey | Territory Added | 
| 14th Century |  |  | Diocese of Dagne (Danj), Albania | Erected | 
| 14th Century |  |  | Apostolic Datary, Roman Curia | Established | 
| 14th Century |  |  | Fratelli Celliti o Alessiani de Aquisgrana | Founded | 
| 15th Century |  |  | Diocese of Montepeloso, Italy | Erected | 
| 15th Century |  |  | Apostolic Signatura, Roman Curia | Established | 
| 16th Century | Congregation for Cardinals Interpreters of the Council of Trent, Roman Curia | Name Changed | Congregation of the Council, Roman Curia | Name Changed | 
| 16th Century | Diocese of Dagne (Danj), Albania | Territory Added | 
| 17th Century |  |  | Archeparchy of Alep [Beroea, Halab] (Maronite), Syria | Erected | 
| 17th Century |  |  | Eparchy of Tripoli del Libano {Tarabulus} (Maronite) | Erected | 
| 17th Century | Diocese of Kisamos (Cisamo), Greece | Territory Added | 
| 17th Century |  |  | Vicariate Apostolic of Asia Minor, Turkey | Erected | 
| 18th Century | Diocese of Prizren, Serbia | Suppressed | Archdiocese of Skopje, North Macedonia | Territory Added | 
| 18th Century |  |  | Titular See of Icosium | Established | 
| 19th Century | Cardinal Titular Church of Sant’Alessio | Name Changed | Cardinal Titular Church of Santi Bonifacio ed Alessio | Name Changed | 
| 19th Century |  |  | Titular See of Tharona | Established |