| Date | Age | Event | Bishop | Title | Current Title |
| 2 May | | Born | Raffaele de Martinis, C.M. † | | Titular Archbishop of Laodicea in Phrygia |
| 66.6 | Died | Matthias Paul Steindl † | Auxiliary Bishop of Wien {Vienna}, Austria |
| 4 May | 67.2 | Died | Vincenzo Ferrari, O.P. † | Bishop of Melfi e Rapolla, Italy |
| 54.3 | Selected | Taddeo Garzilli (Garzillo) † | Bishop of Boiano, Italy | Bishop of Sant’Agata de’ Goti, Italy |
| 55.4 | Selected | Federico Guarini, O.S.B. † | Bishop of Venosa, Italy |
| 71.3 | Died | Adam Korwin Kossakowski † | Auxiliary Bishop of Inflanty (Livonia)-Pilten, Poland |
| 50.2 | Selected | Gennaro Pasca † | Bishop of Nola, Italy | Bishop Emeritus |
| 37.7 | Ordained Bishop | Stjepan Pavlović-Lučić † | Bishop of Kotor (Cattaro), Montenegro |
| 8 May | | Born | Pierre Henri Lamazou † | | Bishop of Amiens, France |
| 11 May | 23.1 | Ordained Priest | Diego Mariano Alguacil y Rodríguez † | Priest | Bishop of Cartagena (en España) |
| 56.6 | Ordained Bishop | Antônio da Arrábida, O.F.M. Ref. † | Titular Bishop of Anemurium |
| 13 May | 22.7 | Ordained Priest | Joseph-Eugène-Bruno Guigues, O.M.I. † | Priest of Oblates of Mary Immaculate | Bishop of Ottawa, Ontario, Canada |
| 15 May | 19.2 | Professed | Louis (de Sainte Thérèse) Martini, O.C.D. † | Member of Order of Discalced Carmelites | Vicar Apostolic Emeritus of Verapoly, India |
| 64.5 | Selected | Giuseppe Maria Pezzella, O.E.S.A. † | Coadjutor Bishop of Calvi e Teano, Italy | Bishop |
| 20 May | 54.0 | Installed | Johann Baptist Judas Thaddeus von Keller † | Bishop of Rottenburg, Germany |
| 21 May | 25.0 | Ordained Priest | Pierre-André Retord, M.E.P. † | Priest | Vicar Apostolic of Western Tonking {Tonkino Occidentale}, Viet Nam |
| 22 May | | Born | Angelo Di Pietro † | | Cardinal, Datary of the Apostolic Datary |
| 25 May | 55.9 | Installed | Antonio Podestá † | Bishop of Saluzzo, Italy |
| 46.4 | Ordained Bishop | Antonio Raimondo Tore † | Bishop of Ales e Terralba, Italy | Archbishop of Cagliari, Italy |
| 57.5 | Ordained Bishop | James Whitfield † | Archbishop of Baltimore, Maryland, USA |
| 27 May | | Born | Matthieu-Victor-Félicien Balaïn, O.M.I. † | | Archbishop of Auch, France |
| 59.9 | Selected | Leonardo Santander y Villavicencio † | Bishop of Astorga, Spain |
| 29 May | 59.5 | Selected | Teofil von Wolicki † | Archbishop of Gniezno e Poznań, Poland |
| 31 May | 24.2 | Ordained Priest | Georges-Claude-Louis-Pie Chalandon † | Priest | Archbishop of Aix (-Arles-Embrun), France |
| 25.3 | Ordained Priest | Auguste Marie Martin † | Priest of Rennes, France | Bishop of Natchitoches, Louisiana, USA |
| 22.6 | Ordained Priest | Jean-Baptiste Pallegoix, M.E.P. † | Priest of La Société des Missions Etrangères | Vicar Apostolic of Eastern Siam {Siam Orientale}, Thailand |
| 23.1 | Ordained Priest | Emmanuel-Jean-François Verrolles, M.E.P. † | Priest | Vicar Apostolic of Liaotung and Manchuria, China |
| 23.0 | Ordained Priest | Luigi Vetta † | Priest | Bishop of Nardò, Italy |
| Jun | 69.6 | Died | Giovanni Baptist Maria Angelini † | Titular Bishop of Megara |
| 83.8 | Resigned | Giulio Maria della Somaglia † | Secretary of State | Cardinal, Librarian of the Vatican Library |
| 2 Jun | 55.0 | Selected | Ignacio Ribes Mayor † | Bishop of Calahorra y La Calzada, Spain | Archbishop of Burgos, Spain |
| 5 Jun | | Born | Georg Ignaz Komp † | | Archbishop of Freiburg im Breisgau, Germany |
| 11 Jun | 66.1 | Died | Bernardino Giovanni Battista Bollati, O.F.M. Obs. † | Bishop of Biella, Italy |
| 47.8 | Selected | Bernardo Antonino Squarcina, O.P. † | Bishop of Ceneda, Italy | Bishop of Adria, Italy |
| 14 Jun | | Born | Kornél Hidasy † | | Bishop of Szombathely, Hungary |
| 15 Jun | 54.8 | Ordained Bishop | Giovanni Maria Bua † | Archbishop of Oristano, Italy |
| 17 Jun | 48.4 | Appointed | Tommaso Bernetti † | Secretary of State | Cardinal, Secretary Emeritus |
| 51.3 | Appointed | Robert Gradwell † | Coadjutor Vicar Apostolic of London District, England, Great Britain |
| 51.3 | Appointed | Robert Gradwell † | Titular Bishop of Lydda | Coadjutor Vicar Apostolic of London District, England, Great Britain |
| 40.7 | Appointed | Myles Murphy † | Bishop of Ossory, Ireland | Bishop of Ferns, Ireland |
| 18 Jun | 64.6 | Resigned | Giuseppe Maria Pezzella, O.E.S.A. † | Bishop of Teramo, Italy | Bishop of Calvi e Teano, Italy |
| 79.6 | Died | Felix von Stubenberg † | Auxiliary Bishop of Eichstätt, Germany |
| 19 Jun | | Born | Francesco d’Albore † | | Bishop Emeritus of Monopoli, Italy |
| 22 Jun | 22.6 | Ordained Priest | Francesco Emilio Cugini † | Priest | Archbishop of Modena (e Nonantola), Italy |
| 23.9 | Ordained Deacon | Nicolò Frangipane † | Deacon | Bishop of Concordia (Sagittaria), Italy |
| 23 Jun | 36.6 | Appointed | Giovanni Battista Bagnasco † | Auxiliary Bishop of Palermo, Italy |
| 36.6 | Appointed | Giovanni Battista Bagnasco † | Titular Bishop of Verinopolis | Auxiliary Bishop of Palermo, Italy |
| 70.7 | Appointed | Albertino Philippe Laurent Marie Bellenghi, O.S.B. † | Titular Archbishop of Nicosia |
| 59.2 | Appointed | Giulio Mariano Carmelo Benzo, O.S.B. † | Auxiliary Bishop of Mazara del Vallo, Italy |
| 59.2 | Appointed | Giulio Mariano Carmelo Benzo, O.S.B. † | Titular Bishop of Constantina | Auxiliary Bishop of Mazara del Vallo, Italy |
| 66.9 | Confirmed | Giuseppe Maria Botticelli, O.M. † | Bishop of Lacedonia, Italy |
| 83.4 | Appointed | Kasper Kazimierz Kolumna Cieciszowski † | Archbishop of Mohilev, Belarus |
| 71.1 | Appointed | Remigio Crescini, O.S.B. † | Cardinal, Bishop of Parma, Italy |
| 63.8 | Confirmed | Paul Louis Joseph D’Hautpoul † | Bishop of Cahors, France | Bishop Emeritus |
| 52.5 | Appointed | Giacomo Filippo Fransoni † | Cardinal-Priest of Santa Maria in Ara Coeli | Cardinal, Prefect of the Congregation for Propagation of the Faith |
| 54.4 | Confirmed | Taddeo Garzilli (Garzillo) † | Bishop of Boiano, Italy | Bishop of Sant’Agata de’ Goti, Italy |
| 71.7 | Appointed | Joachim Józef Grabowski † | Auxiliary Bishop of Mohilev, Belarus | Auxiliary Bishop-Elect |
| 71.7 | Appointed | Joachim Józef Grabowski † | Titular Bishop of Amorium | Auxiliary Bishop-Elect of Mohilev, Belarus |
| 55.5 | Confirmed | Federico Guarini, O.S.B. † | Bishop of Venosa, Italy |
| Born | Jean-François Jamot † | | Bishop of Peterborough, Ontario, Canada |
| 74.3 | Confirmed | Juan Nepomuceno de Lera y Cano † | Bishop of Segovia, Spain |
| 70.5 | Confirmed | Juan Francisco Martínez y Castrillón † | Bishop of Málaga, Spain |
| 52.8 | Appointed | Vincenzo Macioti † | Bishop of Amelia, Italy | Bishop of Ferentino, Italy |
| 70.5 | Appointed | Giuseppe Menditto † | Auxiliary Bishop of Capua, Italy |
| 70.5 | Appointed | Giuseppe Menditto † | Titular Bishop of Callipolis | Auxiliary Bishop of Capua, Italy |
| 58.3 | Confirmed | Tomas Manoel de Noronha e Brito, O.P. † | Bishop of Olinda, Brazil | Bishop Emeritus |
| 71.9 | Appointed | Nicolas-Alexis Ondernard † | Bishop of Namur {Namen}, Belgium |
| 50.4 | Confirmed | Gennaro Pasca † | Bishop of Nola, Italy | Bishop Emeritus |
| 52.3 | Appointed | Ignacy Ludwik Pawłowski † | Auxiliary Bishop of Kamyanets-Podilskyi (Kamieniec), Ukraine | Archbishop of Mohilev, Belarus |
| 52.3 | Appointed | Ignacy Ludwik Pawłowski † | Titular Bishop of Megara | Archbishop of Mohilev, Belarus |
| 64.6 | Appointed | Giuseppe Maria Pezzella, O.E.S.A. † | Titular Bishop of Zela | Bishop of Calvi e Teano, Italy |
| 64.6 | Confirmed | Giuseppe Maria Pezzella, O.E.S.A. † | Coadjutor Bishop of Calvi e Teano, Italy | Bishop |
| 56.7 | Succeeded | Michał Piwnicki † | Bishop of Lutsk and Zhytomyr (Łuck and Zytomierz), Ukraine |
| 74.9 | Appointed | Johann Adam Rieger † | Bishop of Fulda, Germany |
| 40.3 | Confirmed | Louis-François-Auguste de Rohan Chabot † | Archbishop of Auch, France | Cardinal, Archbishop of Besançon, France |
| 60.0 | Confirmed | Leonardo Santander y Villavicencio † | Bishop of Astorga, Spain |
| 62.8 | Appointed | Ferdinando Siciliani † | Auxiliary Bishop of Molfetta, Italy |
| 62.8 | Appointed | Ferdinando Siciliani † | Titular Bishop of Tripolis in Phoenicia | Auxiliary Bishop of Molfetta, Italy |
| 24 Jun | 51.4 | Ordained Bishop | Robert Gradwell † | Titular Bishop of Lydda | Coadjutor Vicar Apostolic of London District, England, Great Britain |
| 26 Jun | | Born | Pelayo González y Conde † | | Bishop of Cuenca, Spain |
| 30 Jun | 38.8 | Appointed | Antonio Peteani (Petrani) † | Bishop of Poreč i Pula, Croatia |
| 1 Jul | 60.5 | Selected | Wincenty Saryusz Karol Skórkowski † | Bishop of Kraków, Poland |
| 2 Jul | 23.2 | Ordained Priest | William Keane † | Priest of Cloyne and Ross, Ireland | Bishop of Cloyne, Ireland |
| Born | José Proceso Pozuelo y Herrero † | | Bishop of Córdoba, Spain |
| 6 Jul | 71.1 | Ordained Bishop | Remigio Crescini, O.S.B. † | Cardinal, Bishop of Parma, Italy |
| 54.5 | Ordained Bishop | Taddeo Garzilli (Garzillo) † | Bishop of Boiano, Italy | Bishop of Sant’Agata de’ Goti, Italy |
| 52.8 | Ordained Bishop | Vincenzo Macioti † | Bishop of Amelia, Italy | Bishop of Ferentino, Italy |
| 7 Jul | | Born | William Benedict Scarisbrick, O.S.B. † | | Bishop Emeritus of Port-Louis, Mauritius |
| 8 Jul | | Born | Jean-Pierre-Bernard Castillon † | | Bishop of Dijon, France |
| 9 Jul | | Born | Luigi Oreglia di Santo Stefano † | | Cardinal, Prefect of the Congregation of Ceremonies |
| 13 Jul | 70.8 | Ordained Bishop | Albertino Philippe Laurent Marie Bellenghi, O.S.B. † | Titular Archbishop of Nicosia |
| 42.5 | Ordained Bishop | Félix Calixto Miranda y Suárez de Figueroa † | Bishop of Cuenca, Ecuador |
| 19 Jul | 73.9 | Died | Bernardo Bernardino Beltrão Freire † | Bishop of Pinhel, Portugal |
| 20 Jul | 61.7 | Selected | Joachim-Jean-Xavier d’Isoard † | Cardinal, Archbishop of Auch, France |
| 40.3 | Selected | Louis-François-Auguste de Rohan Chabot † | Cardinal, Archbishop of Besançon, France |
| 74.4 | Died | Giovanni Francesco Toppia † | Bishop of Vigevano, Italy |
| 56.9 | Ordained Bishop | José Uraga Pérez † | Bishop of Guadix, Spain |
| 25 Jul | 62.9 | Ordained Bishop | Ferdinando Siciliani † | Titular Bishop of Tripolis in Phoenicia | Auxiliary Bishop of Molfetta, Italy |
| 26 Jul | | Born | Laurenz Mayer † | | Auxiliary Bishop of Wien {Vienna}, Austria |
| 27 Jul | 63.9 | Ordained Bishop | Paul Louis Joseph D’Hautpoul † | Bishop of Cahors, France | Bishop Emeritus |
| 10 Aug | 79.7 | Died | Karl Franz von Lodron † | Bishop of Brixen {Bressanone}, Italy |
| 28.0 | Ordained Priest | Karl August von Reisach † | Priest of München und Freising {Munich}, Germany | Cardinal, Archbishop Emeritus |
| 11 Aug | 70.7 | Died | Juan Francisco Martínez y Castrillón † | Bishop of Málaga, Spain |
| 13 Aug | | Born | Joseph-Frédéric Saivet † | | Bishop of Perpignan-Elne, France |
| 18 Aug | 54.0 | Died | Carlo Tommaso Arnosio † | Archbishop of Sassari, Italy |
| 22 Aug | 57.2 | Died | Faustino Zucchini † | Titular Archbishop of Laodicea in Phrygia |
| 23 Aug | 79.4 | Died | Franz Xaver von Neveu † | Bishop of Basel, Switzerland |
| 24 Aug | | Born | Hermann Grüder † | | Prefect of Denmark |
| 25 Aug | 54.8 | Selected | José Asensio Ocón y Toledo † | Bishop of Palencia, Spain | Bishop of Teruel, Spain |
| 31 Aug | | Born | Nicola Zoccoli † | | Auxiliary Bishop of Bologna, Italy |