Date | Country | Change |
| 1202 |  Ireland | Diocese of Clonard was suppressed (to establish Diocese of Meath) |
| 1202 | Ireland | Diocese of Meath was established (from the suppressed Diocese of Clonard and became suffragan of Armagh) |
| 1202 |  Latvia | Diocese of Üxküll was renamed as Diocese of Riga |
| 1203 |  Spain | Diocese of Lérida lost territory to Diocese of Huesca–Jaca |
| 1203.05.07 |  Italy | Archdiocese of Matera was restored (from Metropolitan Archdiocese of Acerenza) |
| 1204 |  Greece | Diocese of Chios was established |
| 1204 | Greece | Diocese of Oleno was established |
| 1204 | Greece | Diocese of Santorini was established |
| 1205 | Greece | Metropolitan Archdiocese of Athens was established (with suffragan sees Aulon, Carystus, Ceo, Coronea, Daulis, Megara, Negroponte, Scyrus and Thermopylæ) |
| 1205 |  Turkiye | Patriarchal See of Constantinople was restored |
| 1206 | Italy | Territorial Prelature of Santa Lucia del Mela was established (from Diocese of Patti and without ecclesiastical province) |
| 1207 | Greece | Diocese of Kefalonia was established (became suffragan of Corinthus) |
| 1207 | Greece | Diocese of Syros was established |
| 1207 | Italy | Diocese of Cuma was suppressed (to Diocese of Aversa and Diocese of Pozzuoli) |
| 1208 | Greece | Diocese of Andros was established (became suffragan of Athens) |
| 1210 | Ireland | Diocese of Mayo was suppressed (to Metropolitan Archdiocese of Tuam) |
| 1211 | Ireland | Diocese of Ardmore was suppressed (to Diocese of Lismore) |
| 1211 | Ireland | Diocese of Ceanannus Mór was suppressed (to Diocese of Meath) |
| 1212 | Greece | Diocese of Milopotamus was established |
| 1212 | Greece | Diocese of Zakynthos was established |
| 1213 |  Estonia | Diocese of Leal was established (from Diocese of Riga) |
| 1213 | Greece | Metropolitan Archdiocese of Crete was established |
| 1215.01.28 |  Germany | Diocese of Chiemsee was established (from Metropolitan Archdiocese of Salzburg) |
| 1215.02.25 | Ireland | Diocese of Glendalough was suppressed (to Metropolitan Archdiocese of Dublin) |
| 1217 | Latvia | Diocese of Semgallia was established (became suffragan of Hamburg–Bremen) |
| 1218 | Estonia | Diocese of Reval was established |
| 1218.01.13 | Italy | Diocese of Terni was restored (from Diocese of Narni and Diocese of Spoleto and without ecclesiastical province) |
| 1218.03.29 |  England | Diocese of Sarum was renamed as Diocese of Salisbury |
| 1218.06.22 |  Austria | Diocese of Seckau was established (from Metropolitan Archdiocese of Salzburg and became suffragan of Salzburg) |
| 1219 |  Egypt | Patriarchal See of Alexandria was demoted as Titular Patriarchal See of Alexandria |
| 1219 | England | Diocese of Bath and Glastonbury was renamed as Diocese of Bath |
| 1219 | Latvia | Diocese of Curland was established (from Diocese of Riga and became suffragan of Hamburg–Bremen) |
| 1219 | Spain | Diocese of San Martiño de Mondoñedo–Dume was renamed as Diocese of Mondoñedo (lost territory to Metropolitan Archdiocese of Braga) |
| 1220 | Estonia | Diocese of Virumaa was established (from Diocese of Riga) |
| 1221.03.26 | Italy | Archpresbyterate nullius of Acquaviva delle Fonti was established (from Metropolitan Archdiocese of Bari e Canosa) |
| 1222.03.11 | Greece | Diocese of Kefalonia was renamed as Diocese of Kefalonia–Zakynthos (gained territory from the suppressed Diocese of Zakynthos) |
| 1222.03.11 | Greece | Diocese of Zakynthos was suppressed (to Diocese of Kefalonia–Zakynthos) |
| 1223 |  France | Diocese of Bethléem à Clamecy was established (from the suppressed Diocese of Bethlehem–Ascalon and became suffragan of Sens) |
| 1223 |  Palestine | Diocese of Bethlehem–Ascalon was suppressed (to establish Diocese of Bethléem à Clamecy) |
| 1224 | Estonia | Diocese of Dorpat was established (from the suppressed Diocese of Leal and became suffragan of Lund) |
| 1224 | Estonia | Diocese of Leal was suppressed (to establish Diocese of Dorpat) |
| 1225 |  Morocco | Diocese of Fez was established |
| 1225 | Morocco | Diocese of Marocco was established (from Metropolitan Archdiocese of Toledo) |
| 1227 | Austria | Territorial Abbacy of Wettingen-Mehrerau was established |
| 1227 | Estonia | Diocese of Virumaa was suppressed |
| 1227 |  Romania | Diocese of Milcovia was established (from Metropolitan Archdiocese of Esztergom) |
| 1227 | Spain | Diocese of Baeza was restored |
| 1228 | Italy | Diocese of Fiesole exchanged territory with Diocese of Firenze |
| 1228 | Italy | Diocese of Firenze exchanged territory with Diocese of Fiesole |
| 1228.05.10 | Austria | Diocese of Lavant was established (from Metropolitan Archdiocese of Salzburg and became suffragan of Salzburg) |
| 1228.10.01 | Estonia | Diocese of Saare-Lääne was established (from Diocese of Dorpat and Diocese of Riga) |
| 1229.01.20 |  Serbia | Diocese of Srijem was restored (from Diocese of Bosnia and became suffragan of Kalocsa) |
| 1230 | Greece | Diocese of Chersonissos was established |
| 1230 | Italy | Metropolitan Archdiocese of Siponto was renamed as Metropolitan Archdiocese of Manfredonia |
| 1230 | Italy | Diocese of Sovana lost territory to Abbacy nullius of Santi Vincenzo ed Anastasio alle Tre Fontane |
| 1230 | Turkiye | Metropolitan Archdiocese of Nicomedia was suppressed |
| 1232 | Spain | Diocese of Calahorra was renamed as Diocese of La Calzada |
| 1234 | Estonia | Diocese of Saare-Lääne was renamed as Diocese of Saare-Lääne |
| 1235 | Spain | Diocese of La Calzada was renamed as Diocese of Calahorra y La Calzada |
| 1236 | Spain | Diocese of Córdoba was restored (from former Diocese of Écija, former Diocese of Egabro, former Diocese of Elvira and former Diocese of Italica) |
| 1237 | Morocco | Diocese of Fez was suppressed (to Diocese of Marocco) |
| 1237.07.15 | Spain | Diocese of Mallorca was restored (from Diocese of Barcelona) |
| 1238 | Spain | Diocese of Segorbe was restored (from Diocese of Albarracin) |
| 1238.10.10 | Spain | Diocese of Valencia was restored (became suffragan of Tarragona) |
| 1239 | England | Diocese of Coventry was renamed as Diocese of Coventry and Lichfield |
| 1239 | Italy | Diocese of Noli was established (from Diocese of Savona and became suffragan of Genova) |
| 1240 | Greece | Diocese of Thermopylæ was suppressed |
| 1240 | Greece | Metropolitan Archdiocese of Thessalonica was suppressed |
| 1240 | Italy | Diocese of Comacchio lost territory to Diocese of Cervia |
| 1240.05.22 | Italy | Diocese of Osimo was suppressed (to establish Diocese of Recanati) |
| 1240.05.22 | Italy | Diocese of Recanati was established (from Diocese of Numana and from the suppressed Diocese of Osimo) |
| 1240.11.15 | Italy | Diocese of Recanati lost territory to Diocese of Numana |
| 1243 | Italy | Diocese of Lodi was suppressed |
| 1243.07.23 |  Poland | Diocese of Warmia was established |
| 1243.07.29 | Poland | Diocese of Chełmno was established (became suffragan of Gniezno) |
| 1243.07.29 | Poland | Diocese of Pomezania was established |
| 1243.07.29 |  Russia | Diocese of Sambia was established |
| 1244.07.19 | France | Diocese of Antibes was renamed as Diocese of Grasse |
| 1245 | Spain | Diocese of Segorbe exchanged territory with Diocese of Valencia |
| 1245 | Spain | Diocese of Valencia exchanged territory with Diocese of Segorbe |
| 1245.01.03 | England | Diocese of Bath was renamed as Diocese of Bath and Wells |
| 1248 | Italy | Archpresbyterate nullius of Altamura was established (from Diocese of Bitetto) |
| 1248 | Italy | Diocese of Tortona lost territory to Metropolitan Archdiocese of Genova |
| 1249 | Spain | Diocese of Baeza was suppressed (to establish Diocese of Jaén) |
| 1249 | Spain | Diocese of Jaén was established (from the suppressed Diocese of Baeza) |
| 1250 |  Albania | Diocese of Butrinto was established |
| 1250 |  Bosnia and Herzegovina | Diocese of Bosnia was suppressed (to establish Diocese of Bosnia) |
| 1250 |  Croatia | Diocese of Bosnia was established (from Diocese of Pécs, from the suppressed Diocese of Bosnia and became suffragan of Ragusa) |
| 1250 | Greece | Diocese of Aulon was suppressed |
| 1250 | Greece | Metropolitan Archdiocese of Gortina was suppressed |
| 1250 | Greece | Metropolitan Archdiocese of Philippi was suppressed |
| 1250 | Greece | Diocese of Retimo was established |
| 1250.06.25 | Spain | Diocese of Barcelona lost territory to Diocese of Mallorca |
| 1250.07.31 | Spain | Diocese of Cartagena was restored (without ecclesiastical province) |
| 1251 | Estonia | Diocese of Saare-Lääne was renamed as Diocese of Saare-Lääne |
| 1251 | Latvia | Diocese of Semgallia was suppressed (to Diocese of Riga) |
| 1251 |  Portugal | Diocese of Silves was restored |
| 1251 | Spain | Metropolitan Archdiocese of Sevilla was restored (with suffragan see Córdoba) |
| 1251.04.01 | Italy | Diocese of Atri was established (from Diocese of Penne) |
| 1252 | Italy | Diocese of Lodi was restored (became suffragan of Milano) |
| 1253 | Greece | Diocese of Milos was established |
| 1253.08 | Ireland | Diocese of Annaghdown was suppressed (to Metropolitan Archdiocese of Tuam) |
| 1254 |  Northern Ireland, Ireland | Diocese of Maghera, Cenél Fearadhaigh and Ardstraw was renamed as Diocese of Derry |
| 1255 | Spain | Diocese of Badajoz was restored (from Metropolitan Archdiocese of Santiago de Compostela and became suffragan of Santiago de Compostela) |
| 1255.01.20 | Latvia | Diocese of Riga was promoted as Metropolitan Archdiocese of Riga (with suffragan sees Chełmno, Curland, Dorpat, Pomezania, Saare-Lääne, Sambia and Warmia) |
| 1256.04.27 | Portugal | Diocese of Coimbra exchanged territory with Diocese of Guarda |
| 1256.04.27 | Portugal | Diocese of Guarda exchanged territory with Diocese of Coimbra and Diocese of Viseu |
| 1256.04.27 | Portugal | Diocese of Viseu exchanged territory with Diocese of Guarda |
| 1257.02.01 | Poland | Diocese of Łuków was established (from Diocese of Kraków) |
| 1257.02.20 | Italy | Diocese of Forconio was suppressed (to establish Diocese of L’Aquila) |
| 1257.02.20 | Italy | Diocese of L’Aquila was established (from Diocese of Rieti and from the suppressed Diocese of Forconio) |
| 1257.08 | Poland | Diocese of Łuków was suppressed (to Diocese of Kraków) |
| 1258.03.18 | Spain | Diocese of Albarracin was suppressed (to Diocese of Segorbe–Albarracín) |
| 1258.03.18 | Spain | Diocese of Segorbe was renamed as Diocese of Segorbe–Albarracín (gained territory from the suppressed Diocese of Albarracin) |
| 1260 |  Cyprus | Metropolitan Archdiocese of Salamis postea Constantia was suppressed |
| 1260 | Italy | Diocese of Nuceria was suppressed (to Metropolitan Archdiocese of Amalfi and Metropolitan Archdiocese of Salerno) |
| 1263.07.27 | Italy | Diocese of Recanati was suppressed (to Diocese of Numana) |
| 1263.08.21 | Spain | Diocese of Cádiz was established (from former Diocese of Asidonia and became suffragan of Sevilla) |
| 1264.03.13 | Italy | Diocese of Osimo was restored (from Diocese of Numana) |
| 1274 | Greece | Metropolitan Archdiocese of Corfù was restored |
| 1279 | Estonia | Diocese of Saare-Lääne was renamed as Diocese of Saare-Lääne |
| 1285 | Italy | Diocese of Gallese was suppressed (to Diocese of Civita Castellana) |
| 1286 | Turkiye | Patriarchal See of Constantinople was demoted as Titular Patriarchal See of Constantinople |
| 1289.12.01 | Italy | Diocese of Recanati was restored (from Diocese of Numana) |
| 1290 | Serbia | Diocese of Graeca Alba was restored |
| 1291.07.21 |  Lebanon | Diocese of Beirut was suppressed |
| 1295 | Palestine, Cyprus,  Israel,  Jordan | Patriarchal See of Jerusalem was demoted as Titular Patriarchal See of Jerusalem |
| 1295.09.16 | France | Diocese of Pamiers was established (from Diocese of Toulouse and became suffragan of Narbonne) |
| 1298.05.01 | Croatia | Diocese of Šibenik was established (from Diocese of Traù and became suffragan of Split) |
| 1300 | Albania | Diocese of Balecio was established |
| 1300 | Albania | Diocese of Benda was established |
| 1300 | Albania | Diocese of Konavlje was established |
| 1300 | Croatia | Diocese of Korcula was established (from Diocese of Hvar and from the suppressed Diocese of Ston) |
| 1300 | Croatia | Diocese of Ston was suppressed (to establish Diocese of Korcula) |
| 1300 | Greece | Diocese of Arcadia was established |
| 1300 | Greece | Diocese of Ario was established |
| 1300 | Greece | Diocese of Carystus was suppressed |
| 1300 | Greece | Diocese of Lango was established |
| 1300 | Greece | Metropolitan Archdiocese of Larissa was demoted as Titular Metropolitan See of Larissa |
| 1300 | Greece | Diocese of Malvasia was suppressed |
| 1300 | Greece | Diocese of Megara was suppressed |
| 1300 | Greece | Diocese of Negroponte was suppressed |
| 1300 | Greece | Diocese of Nisyros was established |
| 1300 | Greece | Titular Metropolitan See of Philippi was restored |
| 1300 | Greece | Diocese of Scyrus was suppressed |
| 1300 |  Iran | Diocese of Diargorgan was established |
| 1300 | Israel | Diocese of San Giovanni d’Acri was demoted as Titular Episcopal See of Akka |
| 1300 | Israel | Metropolitan Archdiocese of Cæsarea was suppressed |
| 1300 | Italy | Abbacy nullius of San Martino al Monte Cimino was established |
| 1300 | Lebanon | Diocese of Byblus was demoted as Titular Episcopal See of Byblus |
| 1300 | Lebanon | Metropolitan Archdiocese of Tyrus was demoted as Titular Metropolitan See of Tyrus |
| 1300 | Russia | Diocese of Tana was established |
| 1300 |  Syria | Archdiocese of Apamea was demoted as Titular Metropolitan See of Apamea |
| 1300 | Syria | Titular Metropolitan See of Damascus was restored |
| 1300 | Syria | Diocese of Laodicea was demoted as Titular Archiepiscopal See of Laodicea |
| 1300 | Turkiye | Titular Episcopal See of Charræ was restored |
| 1300 | Turkiye | Metropolitan Archdiocese of Cyzicus was demoted as Titular Metropolitan See of Cyzicus |
| 1300 | Turkiye | Titular Metropolitan See of Cæsarea Ponti was restored |
| 1300 | Turkiye | Titular Metropolitan See of Ephesus was restored |
| 1300 | Turkiye | Metropolitan Archdiocese of Myra was suppressed |
| 1300 | Turkiye | Diocese of Prusa was suppressed |
