Date | Country | Change |
| 1959 |  Australia | Metropolitan Archdiocese of Melbourne lost territory to Diocese of Sale |
| 1959 |  Canada | Diocese of Bathurst lost territory to Diocese of Saint John, New Brunswick |
| 1959 |  Turkiye | Titular Archiepiscopal See of Myra (Greek-Melkite Rite) was restored |
| 1959.01.10 |  India | Diocese of Changanacherry (Syro-Malabar Rite) was promoted as Metropolitan Archdiocese of Changanacherry (with suffragan see Palai) |
| 1959.01.10 |  Peru | Territorial Prelature of Sicuani was established (from Metropolitan Archdiocese of Cusco and became suffragan of Cusco) |
| 1959.01.17 |  Brazil | Diocese of Patos was established (from Diocese of Cajazeiras and Diocese of Campina Grande and became suffragan of Paraíba) |
| 1959.02.09 |  Central African Republic | Apostolic Prefecture of Bossangoa was established (from Diocese of Berbérati) |
| 1959.02.12 |  Burkina Faso | Apostolic Prefecture of Fada N’Gourma was established (from Apostolic Prefecture of Niamey) |
| 1959.02.16 |  Mexico | Diocese of Sinaloa was renamed as Diocese of Culiacán |
| 1959.02.17 |  Chile | Territorial Prelature of Arica was established (from Diocese of Iquique and became suffragan of La Serena) |
| 1959.02.19 |  Argentina | Ordinariate of Ordinariato para los fieles de ritos orientales en Argentina (Eastern Rite) was established |
| 1959.02.19 |  Chad | Apostolic Prefecture of Moundou was promoted as Diocese of Moundou (became suffragan of Bangui) |
| 1959.02.21 |  Austria | Military Vicariate of Austria was established |
| 1959.03.09 |  Spain | Diocese of Calahorra y La Calzada was renamed as Diocese of Calahorra y La Calzada–Logroño |
| 1959.03.09 | Spain | Diocese of Mondoñedo was renamed as Diocese of Mondoñedo–Ferrol |
| 1959.03.09 | Spain | Diocese of Orihuela was renamed as Diocese of Orihuela–Alicante |
| 1959.03.09 | Spain | Diocese of Osma was renamed as Diocese of Osma–Soria |
| 1959.03.09 | Spain | Diocese of Sigüenza was renamed as Diocese of Sigüenza–Guadalajara |
| 1959.03.09 | Spain | Diocese of Tui was renamed as Diocese of Tui–Vigo |
| 1959.04.01 |  Dominican Republic | Diocese of Nuestra Señora de la Altagracia en Higüey was established (from Metropolitan Archdiocese of Santo Domingo and became suffragan of Santo Domingo) |
| 1959.04.02 |  Botswana | Apostolic Prefecture of Bechuanaland was established (from Diocese of Bulawayo, Diocese of Kimberley and Apostolic Vicariate of Windhoek) |
| 1959.04.02 |  Nigeria | Apostolic Prefecture of Oturkpo was promoted as Diocese of Oturkpo (became suffragan of Lagos) |
| 1959.04.09 |  Zambia | Apostolic Prefecture of Solwezi was established (from Apostolic Vicariate of Ndola) |
| 1959.04.15 | Brazil | Metropolitan Archdiocese of Porto Alegre lost territory to Diocese of Caxias and Diocese of Passo Fundo |
| 1959.04.17 |  Germany,  Denmark,  Finland,  Norway,  Sweden | Apostolic Exarchate of Deutschland und Skandinavien (Ukrainian Rite) was established |
| 1959.04.25 |  Congo-Kinshasa | Apostolic Vicariate of Luebo was established (from Apostolic Vicariate of Luluabourg) |
| 1959.04.25 |  Guinea | Apostolic Prefecture of N’Zérékoré was promoted as Diocese of N’Zérékoré (became suffragan of Conakry) |
| 1959.04.25 |  Malawi | Apostolic Vicariate of Blantyre was promoted as Metropolitan Archdiocese of Blantyre (with suffragan sees Dedza, Lilongwe and Zomba) |
| 1959.04.25 | Malawi | Apostolic Vicariate of Dedza was promoted as Diocese of Dedza (became suffragan of Blantyre) |
| 1959.04.25 | Malawi | Apostolic Vicariate of Lilongwe was promoted as Diocese of Lilongwe (became suffragan of Blantyre) |
| 1959.04.25 | Malawi | Apostolic Vicariate of Zomba was promoted as Diocese of Zomba (became suffragan of Blantyre) |
| 1959.04.25 | Zambia | Apostolic Vicariate of Abercorn was promoted as Diocese of Abercorn (became suffragan of Lusaka) |
| 1959.04.25 | Zambia | Apostolic Vicariate of Fort Jameson was promoted as Diocese of Fort Jameson (became suffragan of Lusaka) |
| 1959.04.25 | Zambia | Apostolic Vicariate of Kasama was promoted as Diocese of Kasama (became suffragan of Lusaka) |
| 1959.04.25 | Zambia | Apostolic Vicariate of Livingstone was promoted as Diocese of Livingstone (became suffragan of Lusaka) |
| 1959.04.25 | Zambia | Apostolic Vicariate of Lusaka was promoted as Metropolitan Archdiocese of Lusaka (with suffragan sees Abercorn, Fort Jameson, Kasama, Livingstone and Ndola) |
| 1959.04.25 | Zambia | Apostolic Vicariate of Ndola was promoted as Diocese of Ndola (became suffragan of Lusaka) |
| 1959.05.04 |  Japan | Diocese of Nagasaki 長崎 was promoted as Metropolitan Archdiocese of Nagasaki 長崎 (with suffragan sees Fukuoka 福岡, Kagoshima 鹿児島, Miyazaki 宮崎 and Okinawa and the Southern Islands 琉球列島) |
| 1959.05.21 |  Madagascar | Diocese of Ambatondrazaka was established (from Metropolitan Archdiocese of Diégo-Suarez and Metropolitan Archdiocese of Tananarive and became suffragan of Tananarive) |
| 1959.05.23 | Mexico | Diocese of San Andrés Tuxtla was established (from Metropolitan Archdiocese of Veracruz–Jalapa and Diocese of Tehuantepec and became suffragan of Veracruz–Jalapa) |
| 1959.05.23 | Mexico | Diocese of Tlaxcala was restored (from Metropolitan Archdiocese of México and Metropolitan Archdiocese of Puebla de los Ángeles and became suffragan of Puebla de los Ángeles) |
| 1959.06.04 | India | Metropolitan Archdiocese of Delhi and Simla was renamed as Metropolitan Archdiocese of Delhi (lost territory to establish Diocese of Simla and gained suffragan see Simla) |
| 1959.06.04 | India | Diocese of Simla was established (from Metropolitan Archdiocese of Delhi and Simla and became suffragan of Delhi) |
| 1959.06.11 |  Burundi | Apostolic Vicariate of Usumbura was established (from Apostolic Vicariate of Kitega and Apostolic Vicariate of Ngozi) |
| 1959.06.11 |  Solomon Islands | Apostolic Vicariate of Western Solomon Islands was established (from Apostolic Vicariate of Northern Solomon Islands and Apostolic Vicariate of South Solomons) |
| 1959.06.18 |  Papua New Guinea | Apostolic Vicariate of Goroka was established (from Apostolic Vicariate of Alexishafen) |
| 1959.06.18 | Papua New Guinea | Apostolic Vicariate of Lae was established (from Apostolic Vicariate of Alexishafen) |
| 1959.06.18 | Papua New Guinea | Apostolic Vicariate of Mount Hagen was established (from Apostolic Vicariate of Alexishafen and Apostolic Vicariate of Wewak) |
| 1959.06.20 | Brazil | Diocese of Campo Mourão was established (from the suppressed Territorial Prelature of Foz do Iguaçu and became suffragan of Curitiba) |
| 1959.06.20 | Brazil | Territorial Prelature of Foz do Iguaçu was suppressed (to establish Diocese of Campo Mourão and Diocese of Toledo) |
| 1959.06.20 | Brazil | Diocese of Santa Cruz do Sul was established (from Metropolitan Archdiocese of Porto Alegre and became suffragan of Porto Alegre) |
| 1959.06.20 | Brazil | Diocese of Toledo was established (from the suppressed Territorial Prelature of Foz do Iguaçu and became suffragan of Curitiba) |
| 1959.06.20 | Chile | Diocese of Los Ángeles was established (from Metropolitan Archdiocese of Concepción and Diocese of Temuco and became suffragan of Concepción) |
| 1959.06.20 | Mexico | Diocese of Ciudad Obregón was established (from Diocese of Sonora and became suffragan of Chihuahua) |
| 1959.06.30 | Congo-Kinshasa | Apostolic Vicariate of Goma was established (from Apostolic Vicariate of Bukavu) |
| 1959.06.30 | Japan | Apostolic Vicariate of Hiroshima 広島 was promoted as Diocese of Hiroshima 広島 |
| 1959.07.16 | Nigeria | Diocese of Kaduna was promoted as Metropolitan Archdiocese of Kaduna (with suffragan sees Jos and Oturkpo) |
| 1959.07.16 | Papua New Guinea | Apostolic Prefecture of Daru was established (from Apostolic Vicariate of Port Moresby) |
| 1959.07.16 | Papua New Guinea | Apostolic Vicariate of Yule Island was established (from Apostolic Vicariate of Port Moresby) |
| 1959.07.18 |  Italy | Diocese of Bova lost territory to Diocese of Gerace–Locri |
| 1959.07.25 |  Eritrea | Apostolic Vicariate of Eritrea was renamed as Apostolic Vicariate of Asmara |
| 1959.07.25 |  USA | Diocese of Galveston was renamed as Diocese of Galveston–Houston |
| 1959.07.26 | Italy | Diocese of Apuania lost territory to Diocese of Brugnato and Diocese of Luni–Sarzana |
| 1959.07.26 | Italy | Diocese of Brugnato exchanged territory with Diocese of Chiavari |
| 1959.07.26 | Italy | Diocese of Chiavari lost territory to Diocese of Luni–Sarzana |
| 1959.08.01 | Italy | Diocese of Ugento was renamed as Diocese of Ugento–Santa Maria di Leuca |
| 1959.09.01 | Mexico | Diocese of Sonora was renamed as Diocese of Hermosillo |
| 1959.10.13 |  Kenya | Apostolic Prefecture of Eldoret was promoted as Diocese of Eldoret (became suffragan of Nairobi) |
| 1959.10.20 |  Indonesia | Apostolic Prefecture of Weetebula was established (from Apostolic Vicariate of Endeh) |
| 1959.10.20 | Kenya | Apostolic Prefecture of Ngong was established (from Metropolitan Archdiocese of Nairobi and Diocese of Kisumu) |
| 1959.11.03 |  Ghana | Diocese of Wa was established (from Diocese of Tamale and became suffragan of Cape Coast) |
| 1959.11.10 | Burundi | Apostolic Vicariate of Kitega was promoted as Metropolitan Archdiocese of Gitega (with suffragan sees Ngozi and Usumbura) |
| 1959.11.10 | Burundi | Apostolic Vicariate of Ngozi was promoted as Diocese of Ngozi (became suffragan of Gitega) |
| 1959.11.10 | Burundi | Apostolic Vicariate of Usumbura was promoted as Diocese of Usumbura (became suffragan of Gitega) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Basankusu was promoted as Diocese of Basankusu (became suffragan of Coquilhatville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Baudouinville was promoted as Diocese of Baudouinville (became suffragan of Elisabethville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Beni in Belgian Congo was promoted as Diocese of Beni in Congo (became suffragan of Bukavu) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Bikoro was promoted as Diocese of Bikoro (became suffragan of Coquilhatville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Boma was promoted as Diocese of Boma (became suffragan of Léopoldville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Bondo was promoted as Diocese of Bondo (became suffragan of Stanleyville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Bukavu was promoted as Metropolitan Archdiocese of Bukavu (with suffragan sees Beni in Congo, Goma, Kasongo and Kindu) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Lac Albert was promoted as Diocese of Bunia (became suffragan of Stanleyville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Buta was promoted as Diocese of Buta (became suffragan of Stanleyville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Coquilhatville was promoted as Metropolitan Archdiocese of Coquilhatville (with suffragan sees Basankusu, Bikoro, Lisala and Molegbe) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Katanga was promoted as Metropolitan Archdiocese of Elisabethville (with suffragan sees Baudouinville, Kamina, Kongolo and Sakania) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Goma was promoted as Diocese of Goma (became suffragan of Bukavu) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Inongo was promoted as Diocese of Inongo (became suffragan of Léopoldville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Ipamu was promoted as Diocese of Ipamu (became suffragan of Léopoldville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Kabinda was promoted as Diocese of Kabinda (became suffragan of Luluabourg) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Lulua was promoted as Diocese of Kamina (became suffragan of Elisabethville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Kasongo was promoted as Diocese of Kasongo (became suffragan of Bukavu) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Kikwit was promoted as Diocese of Kikwit (became suffragan of Léopoldville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Kindu was promoted as Diocese of Kindu (became suffragan of Bukavu) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Kisantu was promoted as Diocese of Kisantu (became suffragan of Léopoldville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Kongolo was promoted as Diocese of Kongolo (became suffragan of Elisabethville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Lisala was promoted as Diocese of Lisala (became suffragan of Coquilhatville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Luebo was promoted as Diocese of Luebo (became suffragan of Luluabourg) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Luluabourg was promoted as Metropolitan Archdiocese of Luluabourg (with suffragan sees Kabinda, Luebo and Tshumbe) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Léopoldville was promoted as Metropolitan Archdiocese of Léopoldville (with suffragan sees Boma, Inongo, Ipamu, Kikwit, Kisantu and Matadi) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Matadi was promoted as Diocese of Matadi (became suffragan of Léopoldville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Ubangui belge was promoted as Diocese of Molegbe (became suffragan of Coquilhatville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Niangara was promoted as Diocese of Niangara (became suffragan of Stanleyville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Sakania was promoted as Diocese of Sakania (became suffragan of Elisabethville) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Stanleyville was promoted as Metropolitan Archdiocese of Stanleyville (with suffragan sees Bondo, Bunia, Buta, Niangara and Wamba) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Tshumbe was promoted as Diocese of Tshumbe (became suffragan of Luluabourg) |
| 1959.11.10 | Congo-Kinshasa | Apostolic Vicariate of Wamba was promoted as Diocese of Wamba (became suffragan of Stanleyville) |
| 1959.11.10 |  Rwanda | Apostolic Vicariate of Kabgayi was promoted as Metropolitan Archdiocese of Kabgayi (with suffragan see Nyundo) |
| 1959.11.10 | Rwanda | Apostolic Vicariate of Nyundo was promoted as Diocese of Nyundo (became suffragan of Kabgayi) |
| 1959.11.13 | Australia | Apostolic Vicariate of Kimberley in Western Australia was renamed as Apostolic Vicariate of Kimberleys |
| 1959.11.14 | Brazil | Diocese of Ruy Barbosa was established (from Metropolitan Archdiocese of São Salvador da Bahia, Diocese of Amargosa, Diocese of Barra, Diocese of Bonfim and Diocese of Caetité and became suffragan of São Salvador da Bahia) |
| 1959.11.17 | Indonesia | Apostolic Prefecture of Sibolga was established (from Apostolic Vicariate of Medan) |
| 1959.11.17 |  Thailand | Apostolic Prefecture of Chieng-Mai was established (from Apostolic Vicariate of Bangkok) |
| 1959.11.21 | Brazil | Diocese of Aterrado exchanged territory with Diocese of Patos de Minas |
| 1959.11.21 | Brazil | Diocese of Patos de Minas exchanged territory with Diocese of Aterrado |
| 1959.12.11 |  Lebanon | Diocese of Sarba (Maronite Rite) was established |
| 1959.12.12 | Brazil | Diocese of Jales was established (from Diocese of Rio Preto and became suffragan of Ribeirão Preto) |
| 1959.12.19 | Indonesia | Apostolic Prefecture of Manokwari was established (from Apostolic Vicariate of Hollandia) |
| 1959.12.19 |  Malaysia | Apostolic Vicariate of Miri was established (from Apostolic Vicariate of Kuching) |
| 1959.12.21 | Spain | Diocese of Astorga exchanged territory with Diocese of Ourense |
| 1959.12.21 | Spain | Diocese of Ourense exchanged territory with Diocese of Astorga |
