| Date | Age | Event | Bishop | Title | Current Title |
| May | | Appointed | Gregory Petros VIII (Michel) Der-Astvadzadourian † | Titular Bishop of Caesarea in Cappadocia degli Armeni | Patriarch of Cilicia (Armenian), Lebanon |
| 1 May | 68.0 | Died | Giovanni Battista de Martino di Pietradoro, C.P.O. † | Bishop of Alife, Italy | Bishop of Telese o Cerreto Sannita, Italy |
| Born | Julian Kuiłovskyi † | | Archbishop of Lviv (Ukrainian), Ukraine |
| 3 May | | Born | Pierre-Paul de Cuttoli † | | Bishop of Ajaccio, France |
| 6 May | 56.0 | Appointed | Vicente Román y Linares, O. Praem. † | Auxiliary Bishop of Sevilla {Seville}, Spain |
| 7 May | 22.5 | Ordained Priest | Bernardino Trionfetti, O.F.M. Obs. † | Priest of Order of Observant Friars Minor | Bishop Emeritus of Terracina, Priverno e Sezze, Italy |
| 8 May | | Born | Ivan Pasteliy (János Pásztélyi) Kovach (Kovács) † | | Bishop of Mukachevo (Munkács) (Ruthenian), Ukraine |
| 10 May | | Born | Bl. Mamerto Esquiú y Medina, O.F.M. Obs. † | | Bishop of Córdoba (Tucumán), Argentina |
| 11 May | 61.8 | Died | Stanislao Sanseverino † | Cardinal, Priest of the Roman Curia - Other |
| 13 May | | Born | Joseph Déruaz † | | Bishop of Lausanne et Genève, Switzerland |
| Born | Henricus (Joseph-Gauthier-Henri) Smeulders, O. Cist. † | | Priest of Order of Cistercians |
| 14 May | | Ordained Bishop | Gregory Petros VIII (Michel) Der-Astvadzadourian † | Titular Bishop of Caesarea in Cappadocia degli Armeni | Patriarch of Cilicia (Armenian), Lebanon |
| 22.6 | Ordained Priest | José Lino de Oliveira † | Priest | Bishop Emeritus of Angola e Congo |
| 48.7 | Ordained Bishop | Ramón Montero † | Titular Archbishop of Hierapolis in Phrygia | Archbishop of Burgos, Spain |
| 15 May | 59.8 | Selected | Carlo Fontanini, C.M. † | Bishop of Concordia (Sagittaria), Italy |
| 20 May | 24.1 | Ordained Priest | Jean-Antoine-Auguste Bélaval † | Priest | Bishop of Pamiers, France |
| 24.1 | Ordained Priest | Antoine Boutonnet † | Priest | Bishop of Guadeloupe et Basse-Terre, Antilles |
| 24.0 | Ordained Priest | Carlo Caccia Dominioni † | Priest of Milano {Milan}, Italy | Auxiliary Bishop |
| 22.5 | Ordained Priest | Carlo Giacinto Luigi Maria Fantini † | Priest | Bishop of Fossano, Italy |
| 23.2 | Ordained Priest | Thomas Furlong † | Priest of Ferns, Ireland | Bishop |
| 23.6 | Ordained Priest | Carlo Macchi † | Priest | Bishop of Reggio Emilia, Italy |
| 23.5 | Ordained Priest | Claude-Marie Magnin † | Priest | Bishop of Annecy, France |
| 26.2 | Ordained Priest | John Baptist Purcell † | Priest | Archbishop of Cincinnati, Ohio, USA |
| 26.2 | Ordained Priest | Louis-Eugène Regnault † | Priest | Bishop of Chartres, France |
| 21 May | 69.4 | Ordained Bishop | Pietro Tasca † | Bishop of Lipari, Italy | Bishop of Cefalù, Italy |
| 23 May | 61.7 | Appointed | John Dubois † | Bishop of New York, New York, USA |
| 50.3 | Ordained Bishop | Plácido Sukias de Somal, C.M.V. † | Titular Archbishop of Siunia | Abbot General of Congregazione Mechitarista di Venezia |
| 53.3 | Appointed | Thomas Weld † | Coadjutor Bishop of Kingston, Ontario, Canada | Cardinal, Coadjutor Bishop Emeritus |
| 53.3 | Appointed | Thomas Weld † | Titular Bishop of Amyclae | Cardinal, Coadjutor Bishop Emeritus of Kingston, Ontario, Canada |
| 25 May | 49.6 | Selected | Cipriano Sánchez Varela † | Bishop of Plasencia, Spain |
| 26 May | | Born | Louis-Taurin Cahagne, O.F.M. Cap. † | | Vicar Apostolic of Galla, Ethiopia |
| 65.3 | Appointed | José Maria de Santa Anna Noronha, O.S.P.P.E. † | Bishop of Angra, Portugal | Bishop of Bragança e Miranda, Portugal |
| 30 May | | Born | Léon-Benoit-Charles Thomas † | | Cardinal, Archbishop of Rouen, France |
| 1 Jun | | Born | Eugène-Louis-Marie Lion, O.P. † | | Apostolic Delegate to Mesopotamia, Kurdistan, and Lesser Armenia, Iraq |
| 3 Jun | 64.6 | Selected | Giovanni De Simone, C.M. † | Bishop of Conversano, Italy |
| 62.9 | Selected | Carlo Puoti † | Archbishop (Personal Title) of Alife, Italy | Bishop |
| 62.9 | Selected | Carlo Puoti † | Archbishop (Personal Title) of Telese o Cerreto Sannita, Italy | Bishop of Alife, Italy |
| 60.6 | Selected | Bernardo Rossi † | Bishop of San Severo, Italy |
| 8 Jun | 74.8 | Died | Henri-Marie-Clauce de Bruc-Montplaisir † | Bishop of Vannes, France |
| 9 Jun | | Appointed | Ignace Haggiuri (Ajjouri), B.A. † | Administrator of Alep [Beroea, Halab] (Melkite Greek), Syria | Bishop of Zahleh e Furzol (Melkite Greek), Lebanon |
| 13 Jun | 65.6 | Died | Agustín Francisco de Otondo Escurruchea, C.O. † | Bishop-Elect of Santa Cruz de la Sierra, Bolivia |
| 16 Jun | 33.4 | Appointed | Thomas Kelly † | Bishop of Dromore, Ireland | Archbishop of Armagh, Ireland |
| 18 Jun | 54.6 | Ordained Bishop | Karl Joseph von Aulock † | Titular Bishop of Marocco o Marruecos, Titular Sees | Auxiliary Bishop of Wrocław (Breslau), Poland |
| 21 Jun | 37.3 | Died | Girolamo Conversini † | Bishop of Cortona, Italy |
| 22 Jun | | Born | Niccolò d’Orgemont de la Fontaine, O.S.B. † | | Abbot of Montecassino, Italy |
| 25 Jun | 94.5 | Died | Domenico Arcaroli † | Bishop of Vieste, Italy | Bishop Emeritus |
| 36.8 | Selected | Antonio Peteani (Petrani) † | Bishop of Poreč (Parenzo), Croatia | Bishop of Poreč i Pula, Croatia |
| 22.5 | Ordained Priest | Franciszek Ksawery Wierzchlejski † | Priest | Archbishop of Lviv, Ukraine |
| 27 Jun | | Born | Frantisek Alojzy Zottmann † | | Bishop Emeritus of Tiraspol, Moldova |
| 28 Jun | | Born | Federico León Aneiros (Aneyros) † | | Archbishop of Buenos Aires, Argentina |
| 29 Jun | 57.0 | Ordained Bishop | Pablo Hernández, O.SS.T. † | Bishop of Ceuta, Spain |
| 30 Jun | 80.5 | Died | Matthäus Georg von Chandelle † | Bishop of Speyer, Germany |
| Jul | 26.5 | Professed | Jacques-Marie-Joseph Jeancard † | Priest of Oblates of Mary Immaculate | Auxiliary Bishop Emeritus of Marseille, France |
| 2 Jul | 60.5 | Ordained Bishop | Francisco Genovés, O.P. † | Bishop of Cebu, Philippines |
| 41.3 | Resigned | Carlo Odescalchi, S.J. † | Archbishop of Ferrara, Italy | Priest of Society of Jesus |
| 3 Jul | 47.3 | Appointed | Vincenzo Annovazzi † | Auxiliary Bishop of Civitavecchia, Italy | Bishop Emeritus of Anagni, Italy |
| 47.3 | Appointed | Vincenzo Annovazzi † | Titular Bishop of Lerus | Bishop Emeritus of Anagni, Italy |
| 62.3 | Appointed | Karl Adalbert von Beyer, O. Praem. † | Auxiliary Bishop of Köln {Cologne}, Germany |
| 62.3 | Appointed | Karl Adalbert von Beyer, O. Praem. † | Titular Bishop of Sebaste in Palaestina | Auxiliary Bishop of Köln {Cologne}, Germany |
| 60.8 | Confirmed | Philibert de Bruillard † | Bishop of Grenoble, France | Bishop Emeritus |
| 31.6 | Appointed | Ignazio Giovanni Cadolini † | Bishop of Cervia, Italy | Cardinal, Archbishop of Ferrara, Italy |
| 60.7 | Appointed | Bartolomeo Alberto (Mauro) Cappellari, O.S.B. † | Cardinal-Priest of San Callisto | Pope (Roma {Rome}, Italy) |
| 58.9 | Appointed | Filippo Cattani † | Bishop of Reggio Emilia, Italy |
| 39.5 | Confirmed | Estevam a Jesu Maria da Costa, O.F.M. Ref. † | Bishop of São Tomé of Meliapore, India | Bishop of Angra, Portugal |
| 34.2 | Appointed | Filippo de Angelis † | Coadjutor Bishop of Corneto (Tarquinia) e Montefiascone, Italy | Cardinal, Archbishop of Fermo, Italy |
| 34.2 | Appointed | Filippo de Angelis † | Titular Bishop of Leuce | Cardinal, Archbishop of Fermo, Italy |
| 64.7 | Confirmed | Hilarión Diéz Fernández, O.S.A. † | Archbishop of Manila, Philippines |
| 64.7 | Confirmed | Giovanni De Simone, C.M. † | Bishop of Conversano, Italy |
| 31.7 | Appointed | Chiarissimo Falconieri Mellini † | Cardinal, Archbishop of Ravenna, Italy |
| 72.8 | Appointed | Filippo Filonardi † | Archbishop of Ferrara, Italy |
| Appointed | Giorgio Gabinelli † | Bishop of Tinos and Mykonos, Greece | Bishop Emeritus |
| 50.1 | Appointed | Jan Marceli Gutkowski † | Bishop of Janów Podlaski (Podlaska o Janów), Poland | Bishop Emeritus |
| 55.7 | Confirmed | Friedrich Klemens von Ledebur-Wicheln † | Bishop of Paderborn, Germany |
| 42.8 | Appointed | Franciszek Ignacy Lewiński † | Auxiliary Bishop of Janów Podlaski (Podlaska o Janów), Poland |
| 42.8 | Appointed | Franciszek Ignacy Lewiński † | Titular Bishop of Eleutheropolis in Macedonia | Auxiliary Bishop of Janów Podlaski (Podlaska o Janów), Poland |
| Appointed | Francesco da Leonessa, O.F.M. Ref. † | Bishop of Santorini {Thira}, Greece | Former Bishop-Elect |
| 50.7 | Appointed | Ludovico Micara, O.F.M. Cap. † | Cardinal-Priest of Santi Quattro Coronati | Cardinal, Cardinal-Bishop of Ostia (e Velletri) |
| 69.6 | Appointed | Giuseppe de Nobili † | Archbishop of Lucca, Italy |
| 46.4 | Appointed | Gaspare Bernardo Pianetti † | Bishop of Viterbo e Tuscania, Italy | Cardinal, Bishop Emeritus |
| 54.7 | Appointed | Michał Piwnicki † | Coadjutor Bishop of Lutsk and Zhytomyr (Łuck and Zytomierz), Ukraine | Bishop |
| 54.7 | Appointed | Michał Piwnicki † | Titular Bishop of Ramata (Rama) | Bishop of Lutsk and Zhytomyr (Łuck and Zytomierz), Ukraine |
| 63.0 | Confirmed | Carlo Puoti † | Archbishop (Personal Title) of Alife, Italy | Bishop |
| 63.0 | Confirmed | Carlo Puoti † | Archbishop (Personal Title) of Telese o Cerreto Sannita, Italy | Bishop of Alife, Italy |
| 68.3 | Appointed | Agostino Rivarola † | Cardinal-Deacon of Santa Maria ad Martyres | Cardinal, Priest of Roma {Rome}, Italy |
| 60.7 | Confirmed | Bernardo Rossi † | Bishop of San Severo, Italy |
| 49.7 | Confirmed | Cipriano Sánchez Varela † | Bishop of Plasencia, Spain |
| 50.8 | Appointed | Giovanni Battista Sartori Canova † | Titular Bishop of Myndus |
| 43.3 | Appointed | Francesco Serra Cassano † | Coadjutor Archbishop of Capua, Italy | Cardinal, Archbishop |
| 62.5 | Appointed | Francisco Spolverini † | Auxiliary Bishop of Sabina (-Farfa), Italy |
| 62.5 | Appointed | Francisco Spolverini † | Titular Bishop of Diocletianopolis in Palaestina | Auxiliary Bishop of Sabina (-Farfa), Italy |
| 9 Jul | 47.3 | Ordained Bishop | Vincenzo Annovazzi † | Titular Bishop of Lerus | Bishop Emeritus of Anagni, Italy |
| 72.2 | Installed | Mikołaj Jan Manugiewicz † | Bishop of Sejny o Sejna o Augustów, Poland |
| 69.7 | Ordained Bishop | Giuseppe de Nobili † | Archbishop of Lucca, Italy |
| 60.7 | Ordained Bishop | Bernardo Rossi † | Bishop of San Severo, Italy |
| 11 Jul | 89.9 | Died | Charles-François d’Aviau Du Bois-de-Sanzay † | Archbishop of Bordeaux, France |
| Born | James Rogers † | | Bishop Emeritus of Chatham, New Brunswick, Canada |
| 15 Jul | 46.8 | Appointed | José Maria de Macerata, O.F.M. Cap. † | Bishop of Cuiabá, Brazil | Former Bishop-Elect |
| 16 Jul | | Born | Carlo Bertuzzi † | | Bishop Emeritus of Foligno, Italy |
| 17 Jul | | Born | Michel-Esther Leturdu, M.E.P. † | | Vicar Apostolic of Malacca-Singapore |
| 76.6 | Died | José Valério da Cruz, C.O. † | Bishop of Portalegre, Portugal |
| 18 Jul | 37.5 | Appointed | Joseph Rosati, C.M. † | Apostolic Administrator of Saint Louis, Missouri, USA | Bishop |
| 37.5 | Appointed | Joseph Rosati, C.M. † | Apostolic Administrator of New Orleans, Louisiana, USA | Bishop of Saint Louis, Missouri, USA |
| 83.5 | Died | Francesco Giovanni Scutellari Ajani † | Titular Bishop of Ioppe |
| 22 Jul | 60.5 | Selected | Johann Martin Manl † | Bishop of Speyer, Germany | Bishop of Eichstätt, Germany |
| 23 Jul | 34.2 | Ordained Bishop | Filippo de Angelis † | Titular Bishop of Leuce | Cardinal, Archbishop of Fermo, Italy |
| 22.5 | Ordained Priest | Emidio Foschini † | Priest | Bishop of Città della Pieve, Italy |
| 62.5 | Ordained Bishop | Francisco Spolverini † | Titular Bishop of Diocletianopolis in Palaestina | Auxiliary Bishop of Sabina (-Farfa), Italy |
| 25 Jul | | Born | Augustin Planque, S.M.A. † | | Superior General of Society of African Missions |
| 26 Jul | 87.9 | Died | [André Champsaud] † | Bishop Emeritus of [Basses-Alpes (Constitutional), France] |
| 76.5 | Died | Baldassare Mormile, C.R. † | Archbishop of Capua, Italy |
| 43.4 | Succeeded | Francesco Serra Cassano † | Cardinal, Archbishop of Capua, Italy |
| 28 Jul | 75.7 | Installed | Pedro Gutiérrez de Cos y Saavedra Seminario † | Bishop of Puerto Rico (Porto Rico) |
| 55.7 | Ordained Priest | Friedrich Klemens von Ledebur-Wicheln † | Priest | Bishop of Paderborn, Germany |
| 30 Jul | 62.5 | Died | Bonaventura Zabberoni, O.F.M. Conv. † | Vicar Apostolic of Moldavia |
| 4 Aug | | Born | Marutha Pierre Topal † | | Patriarchal Vicar of Diarbekir (Amida) (Syrian), Turkey |
| 6 Aug | 60.9 | Ordained Bishop | Philibert de Bruillard † | Bishop of Grenoble, France | Bishop Emeritus |
| 24.0 | Ordained Priest | John Pius Leahy, O.P. † | Priest of Order of Friars Preachers | Bishop of Dromore, Ireland |
| 53.5 | Ordained Bishop | Thomas Weld † | Titular Bishop of Amyclae | Cardinal, Coadjutor Bishop Emeritus of Kingston, Ontario, Canada |
| 13 Aug | 58.5 | Selected | Jean-Louis Anne Madelain Lefebvre de Cheverus † | Cardinal, Archbishop of Bordeaux, France |
| 61.0 | Selected | Simon Garnier † | Bishop of Vannes, France |
| 22.9 | Ordained Priest | Antoine-Matthias-Alexandre Jacquemet † | Priest | Bishop of Nantes, France |
| 15 Aug | 31.8 | Ordained Bishop | Chiarissimo Falconieri Mellini † | Cardinal, Archbishop of Ravenna, Italy |
| 46.5 | Ordained Bishop | Gaspare Bernardo Pianetti † | Bishop of Viterbo e Tuscania, Italy | Cardinal, Bishop Emeritus |
| 19 Aug | 56.5 | Died | Carlo Cavalieri Manassi † | Bishop of Terracina, Priverno e Sezze, Italy |
| 20 Aug | 60.6 | Selected | Louis-Guillaume-Valentin Dubourg, P.S.S. † | Bishop of Montauban, France | Archbishop of Besançon, France |
| 16.0 | Professed | Bonfiglio Mura, O.S.M. † | Member of Order of Friar Servants of Mary | Archbishop of Oristano, Italy |
| 22 Aug | | Born | Alessandro Maria Basile, C.Ss.R. † | | Bishop of Cassano all’Jonio, Italy |
| 23.1 | Ordained Deacon | Antoni Józef Manastyrski † | Deacon | Bishop of Przemyśl, Poland |
| 24 Aug | 24.4 | Ordained Deacon | Manuel Ángel del Prado Cárdenas † | Deacon | Archbishop of La Plata o Charcas, Bolivia |
| 26 Aug | 22.4 | Ordained Priest | Teobaldo (Vincentius Joseph Cirillus) Cesari, O. Cist. † | Priest of Order of Cistercians | Abbot General Emeritus |
| 27 Aug | 24.5 | Ordained Priest | Manuel Ángel del Prado Cárdenas † | Priest | Archbishop of La Plata o Charcas, Bolivia |
| 33.6 | Ordained Bishop | Thomas Kelly † | Bishop of Dromore, Ireland | Archbishop of Armagh, Ireland |
| 23.2 | Ordained Priest | Antoni Józef Manastyrski † | Priest | Bishop of Przemyśl, Poland |
| 28 Aug | 77.7 | Died | [Noël-Gabriel-Luce de Villar] † | Bishop Emeritus of [Mayenne (Constitutional), France] |