| Date | Age | Event | Bishop | Title | Current Title |
| 1 May | | Born | Thomas-Marie-Joseph Gousset † | | Cardinal, Archbishop of Reims, France |
| 45.8 | Ordained Bishop | Jean-Siffrein Maury † | Titular Archbishop of Nicaea | Cardinal, Bishop Emeritus of Corneto (Tarquinia) e Montefiascone, Italy |
| 3 May | 72.2 | Installed | Gaetano Maria Capece, C.R. † | Archbishop (Personal Title) of Pozzuoli, Italy | Bishop |
| 4 May | 66.5 | Died | Giuseppe Garampi † | Cardinal, Bishop of Corneto (Tarquinia) e Montefiascone, Italy |
| 12 May | | Born | Joannes Kraly † | | Auxiliary Bishop of Zagreb, Croatia |
| 13 May | | Born | Bl. Giovanni Maria Mastai-Ferretti † | | Pope (Roma {Rome}, Italy) |
| 20 May | 62.4 | Ordained Bishop | Giuseppe Domenico Porqueddu † | Bishop of Iglesias, Italy |
| 21 May | 68.1 | Died | Agustín Benito Torres, O. Carm. † | Bishop of Albarracin, Spain |
| 22 May | 83.4 | Died | Giuseppe Luigi Avogadro, C.R.L. † | Bishop of Casale Monferrato, Italy |
| 24 May | 51.0 | Installed | Vincenzo Maria Morelli, C.R. † | Archbishop of Otranto, Italy |
| 26 May | 51.5 | Elected | Carlo Francesco Maria Caselli, O.S.M. † | Prior General of Order of Friar Servants of Mary | Cardinal, Bishop of Parma, Italy |
| 27 May | 65.6 | Ordained Bishop | Francisco de Ibarra y Herrera † | Bishop of Guayana, Venezuela | Archbishop of Caracas, Santiago de Venezuela |
| 2 Jun | | Born | Gaspard-Joseph Labis † | | Bishop of Tournai {Doornik}, Belgium |
| 43.2 | Selected | Franz Xaver von Neveu † | Bishop of Basel, Switzerland |
| 24.4 | Ordained Priest | Francisco de Săo Damazo Abreu Vieira, O.F.M. Obs. † | Priest of Order of Observant Friars Minor | Archbishop of Săo Salvador da Bahia, Brazil |
| 3 Jun | 66.4 | Ordained Bishop | Andrés Ambrosio de Llanos y Valdés, O.F.M. † | Bishop of Linares o Nueva León, Nuevo León, México |
| 67.7 | Died | César Constantin François de Hoensbroeck † | Bishop of Ličge, Belgium |
| 22.2 | Ordained Deacon | Grzegorz Tomasz Ziegler, O.S.B. † | Deacon | Bishop of Linz, Austria |
| 9 Jun | 84.2 | Resigned | Alberto Maria (Leonardo Antonio Pasquale) Capobianco, O.P. † | Archbishop of Reggio Calabria, Italy | Archbishop Emeritus |
| 10 Jun | 22.9 | Ordained Priest | Antonio Savorin † | Priest | Bishop of Chioggia, Italy |
| 13 Jun | 47.3 | Selected | Enrico Capece Minutolo, C.O. † | Bishop of Mileto, Italy |
| 15 Jun | 68.2 | Died | Luis Velasco y Maeda, O.F.M. Obs. † | Bishop of Paraguay (o Ssma Assunzione) |
| 16 Jun | | Born | Juan Francisco Escalante y Moreno † | | Auxiliary Bishop of Sonora, México |
| 17 Jun | 69.2 | Died | Johann Georg Joseph von Eckart † | Auxiliary Bishop of Mainz, Germany |
| 75.8 | Died | Rafael Lasala y Locela, O.S.A. † | Bishop of Solsona, Spain |
| 18 Jun | 52.8 | Confirmed | Agostino Andriani † | Bishop of Mottola (Motula), Italy |
| 53.9 | Appointed | Theodor (Johann Karl) von Brabeck, O.S.B. † | Bishop of Corvey, Germany |
| 47.4 | Confirmed | Enrico Capece Minutolo, C.O. † | Bishop of Mileto, Italy |
| 84.2 | Appointed | Alberto Maria (Leonardo Antonio Pasquale) Capobianco, O.P. † | Titular Archbishop of Colossae | Archbishop Emeritus of Reggio Calabria, Italy |
| 59.0 | Elevated to Cardinal | Giovanni Battista Caprara Montecuccoli † | Cardinal, Archbishop of Milano {Milan}, Italy |
| 51.9 | Confirmed | Michele de Angelis † | Bishop of Gravina (di Puglia), Italy |
| 46.7 | Appointed | Remigio de La Santa y Ortega † | Bishop of Panamá | Bishop of Lérida, Spain |
| 24.2 | Ordained Priest | Józef Marcelin Dzięcielski † | Priest | Bishop of Lublin, Poland |
| 64.5 | Confirmed | Gaetano Maria Garrasi, O.E.S.A. † | Archbishop of Messina, Italy |
| 54.5 | Confirmed | Salvatore Gonnelli † | Bishop of Venosa, Italy |
| 56.8 | Appointed | Johann Maximilian von Haunold † | Auxiliary Bishop of Mainz, Germany |
| 56.8 | Appointed | Johann Maximilian von Haunold † | Titular Bishop of Emmaüs | Auxiliary Bishop of Mainz, Germany |
| 55.6 | Confirmed | Pasquale Martini † | Bishop of Cittŕ Ducale, Italy |
| 63.7 | Confirmed | Niccolň Angelo Sagredo † | Archbishop (Personal Title) of Torcello (Turris), Italy | Bishop |
| 60.1 | Appointed | Giovanni Luca Solari † | Bishop of Brugnato, Italy |
| 66.5 | Confirmed | Anselmo Maria Toppi, O.S.B. † | Bishop of Termoli, Italy |
| 65.5 | Confirmed | Luigi Trasmondi, O.S.B. † | Archbishop of Trani, Italy |
| 56.5 | Confirmed | Lorenzo Maria (Pietro Felice) Varano, O.P. † | Bishop of Bisignano, Italy |
| 52.6 | Confirmed | Angelo Maria (Giuseppe Caesar Augustus) Vassalli, O.S.B. † | Bishop of Massa Lubrense, Italy |
| 21 Jun | 78.3 | Died | Pietro Paolo Leonardi † | Bishop of Ascoli Piceno, Italy |
| 24 Jun | 52.8 | Ordained Bishop | Agostino Andriani † | Bishop of Mottola (Motula), Italy |
| 47.4 | Ordained Bishop | Enrico Capece Minutolo, C.O. † | Bishop of Mileto, Italy |
| 61.4 | Ordained Bishop | [André François Chaussy] † | Bishop |
| 51.9 | Ordained Bishop | Michele de Angelis † | Bishop of Gravina (di Puglia), Italy |
| 64.5 | Ordained Bishop | Gaetano Maria Garrasi, O.E.S.A. † | Archbishop of Messina, Italy |
| 54.5 | Ordained Bishop | Salvatore Gonnelli † | Bishop of Venosa, Italy |
| 23.8 | Ordained Priest | Hugues-Robert-Jean-Charles de la Tour d’Auvergne-Lauraquais † | Priest | Cardinal, Bishop of Arras, France |
| 55.6 | Ordained Bishop | Pasquale Martini † | Bishop of Cittŕ Ducale, Italy |
| 34.5 | Ordained Bishop | [Joseph Perbost] † | Bishop |
| 24.0 | Ordained Priest | Etienne Blanquet de Rouville † | Priest | Auxiliary Bishop of Reims, France |
| 60.1 | Ordained Bishop | Giovanni Luca Solari † | Bishop of Brugnato, Italy |
| 66.5 | Ordained Bishop | Anselmo Maria Toppi, O.S.B. † | Bishop of Termoli, Italy |
| 65.5 | Ordained Bishop | Luigi Trasmondi, O.S.B. † | Archbishop of Trani, Italy |
| 56.5 | Ordained Bishop | Lorenzo Maria (Pietro Felice) Varano, O.P. † | Bishop of Bisignano, Italy |
| 52.6 | Ordained Bishop | Angelo Maria (Giuseppe Caesar Augustus) Vassalli, O.S.B. † | Bishop of Massa Lubrense, Italy |
| 8 Jul | 22.0 | Ordained Priest | Anton Alois Buchmayer † | Priest of Sankt Pölten, Austria | Bishop |
| 17 Jul | 55.9 | Died | Cayetano Franco y Monroy † | Archbishop of Guatemala |
| 19 Jul | | Born | Pio Vincenzo Forzani † | | Bishop of Vigevano, Italy |
| 20 Jul | 43.3 | Appointed | Thomas Bray † | Archbishop of Cashel (-Emly), Ireland |
| 24 Jul | | Born | Ignác Fábry † | | Bishop of Košice, Slovakia |
| 26 Jul | 23.1 | Ordained Priest | László Esterházy † | Priest | Bishop of Rožňava, Slovakia |
| 2 Aug | | Born | Ferenc Szaniszlň de Torda † | | Bishop Emeritus of Oradea Mare {Gran Varadino, Nagyvárad}, Romania |
| 46.7 | Selected | Pietro Antonio Zorzi, C.R.S. † | Cardinal, Archbishop of Udine, Italy |
| 3 Aug | | Born | Marie-Dominique-Auguste Sibour † | | Archbishop of Paris, France |
| 7 Aug | 91.3 | Died | Antonio Alcalde y Barriga, O.P. † | Bishop of Guadalajara, Jalisco, México |
| 12 Aug | 23.0 | Ordained Priest | József de Belánsky † | Priest | Bishop of Banská Bystrica, Slovakia |
| 45.4 | Ordained Priest | Giovanni Filippo Gallarati Scotti † | Priest | Cardinal, Cardinal-Priest of San Lorenzo in Lucina |
| 14 Aug | | Born | Ambrogio Campodonico † | | Apostolic Nuncio |
| 16 Aug | 36.1 | Selected | François-Antoine-Marie-Constantin de Méan et de Beaurieux † | Bishop of Ličge, Belgium | Archbishop of Mechelen, Belgium |
| 18 Aug | | Born | Joaquín Barbajero y Villar † | | Bishop of León, Spain |
| 20 Aug | 22.7 | Ordained Deacon | János Horváth † | Deacon | Bishop of Székesfehérvár (Albareale), Hungary |
| 27 Aug | | Born | Federico Manfredini † | | Bishop of Padova {Padua}, Italy |
| 28 Aug | 37.0 | Appointed | Cesare Brancadoro † | Apostolic Nuncio to Flanders, Belgium | Cardinal, Archbishop of Fermo, Italy |
| 29 Aug | | Born | Juan José de Aycinena y Pińol † | | Auxiliary Bishop of Guatemala |
| 30 Aug | | Born | Pierre-Jean-Mathias Loras † | | Bishop of Dubuque, Iowa, USA |