O'Higgins, Ambrose and Bernard
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11225c.htm

Ogdensburg, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11222a.htm

Our Lady of the Snow
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11361c.htm

O'Braein, Tighernach
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11193a.htm

Obedience, Religious
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11182a.htm

O'Queely, Malachias
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11264b.htm

O'Reilly, Bernard
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11293b.htm

Ostensorium (Monstrance)
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11344a.htm

O Antiphons
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11173b.htm

Oregon City
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11293a.htm

Ostrogoths
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11347d.htm

Ostracine
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11347b.htm

Obedience
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11181c.htm

Ontology
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11258a.htm

Oran
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11266a.htm

Original Sin
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11312a.htm

Oriani, Barnaba
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11302b.htm

O'Conor, Charles
The son of Irish immigrants, he was an eminent New York lawyer and orator. He defended Jefferson Davis and prosecuted Boss Tweed. Died 1884.
http://www.newadvent.org/cathen/11202a.htm

Ozias
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11379a.htm

Oakeley, Frederick
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11173a.htm

O'Devany, Cornelius
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11207a.htm

Odilo, Saint
Abbot of Cluny. He died in 1048.
http://www.newadvent.org/cathen/11207c.htm

Odin, John Mary
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11208a.htm

Odo, Saint
Benedictine monk, Archbishop of Canterbury, died in 959.
http://www.newadvent.org/cathen/11209b.htm

Odo of Canterbury
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11211b.htm

Oresme, Nicole
Article by Pierre Duhem on this medieval scientific thinker.
http://www.newadvent.org/cathen/11296a.htm

Ostraka, Christian
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11347c.htm

O'Cullenan, Gelasius
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11205a.htm

Obligation
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11189a.htm

Obreption
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11193c.htm

O'Bruadair, David
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11193e.htm

Olier, Jean-Jacques
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11240d.htm

Obba
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11181b.htm

Oettingen
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11215b.htm

Oggione, Marco D'
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11223a.htm

Oria
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11302a.htm

Ossat, Arnaud d'
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11342a.htm

O'Fihely, Maurice
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11221a.htm

Oxford, University of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11365c.htm

O'Dwyer, Joseph
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11212d.htm

O Filii et Filiae
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11221b.htm

Oertel, John James Maximilian
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11215a.htm

Offa
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11215c.htm

O'Herlahy, Thomas
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11225b.htm

Ohler, Aloys Karl
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11228a.htm

Obazine, Monastery of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11181a.htm

Occasionalism
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11195b.htm

Oecumenius
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11214b.htm

O'Hussey, Maelbrighte
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11228c.htm

Occasions of Sin
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11196a.htm

Ojeda, Alonso de
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11230a.htm

Oxford Movement, The (1833-1845)
Lengthy historical article on the Tractarian Movement includes information on John Henry Newman, as well as on other leading lights of this nineteenth-century Anglo-Catholic campaign, such as John Keble and Hurrell Froude.
http://www.newadvent.org/cathen/11370a.htm

Option, Right of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11264a.htm

Olah, Nicolaus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11234b.htm

Old Hall (St. Edmund's College)
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11239a.htm

Okeghem, Jean d'
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11230b.htm

Oldenburg
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11237b.htm

Oecolampadius, John
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11213a.htm

Oil of Saints
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11228d.htm

Offertory
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11217a.htm

Octavarium Romanum
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11203b.htm

Omaha, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11249b.htm

Oremus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11295a.htm

Ontario
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11254a.htm

Ordeals
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11276b.htm

Obregonians
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11193b.htm

Olivet, Mount
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11244b.htm

O'Hurley, Dermond
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11228b.htm

Oaths
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11176a.htm

O'Hely, Patrick
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11225a.htm

Omission
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11251b.htm

Oeconomus, Episcopal
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11214a.htm

Oblate Sisters of Providence
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11184a.htm

Onias
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11253b.htm

Optimism
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11263a.htm

Old Chapter, The
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11236a.htm

Ossory, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11342b.htm

Octave
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11204a.htm

Ohio
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11225d.htm

Ophir
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11259b.htm

O'Neill, Hugh
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11252a.htm

Oaths, English Post-Reformation
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11177a.htm

Our Lady of Good Counsel, Feast of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11361a.htm

Oostacker, Shrine of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11259a.htm

Olympus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11249a.htm

Oates's Plot
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11173c.htm

Office of the Dead
Historical article on a special set of prayers for the deceased.
http://www.newadvent.org/cathen/11220a.htm

Omnipotence
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11251c.htm

Oracle
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11264c.htm

Occult Art, Occultism
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11197b.htm

Ordinariate
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11284a.htm

Ontologism
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11257a.htm

O'Neill, Owen Roe
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11253a.htm

Oregon
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11288a.htm

Orate Fratres
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11269b.htm

Ointment in Scripture
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11229a.htm

Otto of St. Blasien
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11360a.htm

Orders, Holy
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11279a.htm

Ozanam, Antoine-Frédéric
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11378a.htm

O'Brien, Terence Albert
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11193d.htm

Olivetans
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11244c.htm

Orihuela
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11315a.htm

Ostiensis
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11347a.htm

O'Loghlen, Michael
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11248a.htm

Oriental Study and Research
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11302c.htm

Osimo
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11338a.htm

Orbellis, Nicolas d'
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11275a.htm

Osnabrück, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11341a.htm

Oriflamme
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11306a.htm

O Salutaris Hostia
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11334a.htm

Odense, Ancient See of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/16064d.htm

Orans
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11269a.htm

Orientation of Churches
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11305a.htm

Oswald, Saint
King of Northumbria and martyr, d. 642.
http://www.newadvent.org/cathen/11348c.htm

Oswin, Saint
Biography of the king and martyr, who was murdered in 651.
http://www.newadvent.org/cathen/11349a.htm

Otfried of Weissenburg
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11350a.htm

Otranto
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11351c.htm

Oslo, Ancient See of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/16065a.htm

Our Lady of the Fields, Brothers of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11361b.htm

Overbeck, Friedrich
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11362a.htm

Oaxaca
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11180a.htm

Oratory, French Congregation of the
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11274a.htm

Our Lady, Help of Christians, Feast of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11360c.htm

Oratory of Saint Philip Neri, The
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11272a.htm

Oscott (St. Mary's College)
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11335c.htm

Otho, Marcus Salvius
Details on the reign of Roman Emperor.
http://www.newadvent.org/cathen/11351b.htm

Obedientiaries
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11183a.htm

O'Sullivan Beare, Philip
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11348a.htm

Oxenford, John
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11364b.htm

Oblates of Mary Immaculate
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11184b.htm

Oblates of Saint Francis de Sales
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11187a.htm

Oblati, Oblatae, Oblates
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11188a.htm

O'Callaghan, Edmund Bailey
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11194a.htm

O'Carolan, Torlogh
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11195a.htm

O'Conor, Charles
Called "the Venerable." Eighteenth-century Irish antiquarian.
http://www.newadvent.org/cathen/11203a.htm

O'Curry, Eugene
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11205b.htm

O'Daly, Daniel
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11205c.htm

O'Daly, Donogh Mór
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11206a.htm

Odescalchi, Carlo
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11206b.htm

O Deus Ego Amo Te
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11206c.htm

Odilia, Saint
Patroness of Alsace, d. 720, founded the convent of Hohenburg.
http://www.newadvent.org/cathen/11207b.htm

Odington, Walter
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11208b.htm

Odo of Cambrai, Blessed
Benedictine abbot, bishop of Cambrai, exiled for political reasons, d. 1113.
http://www.newadvent.org/cathen/11211a.htm

Odo of Cheriton
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11212a.htm

Odo of Glanfeuil
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11212b.htm

Odo, Saint
Second abbot of Cluny, died 942.
http://www.newadvent.org/cathen/11209a.htm

O'Donnell, Edmund
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11210b.htm

O'Donovan, John
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11210c.htm

O'Dugan, John
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11212c.htm

Offerings
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11215d.htm

Ogliastra
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11223c.htm

O'Growney, Eugene
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11224a.htm

O'Hagan, John
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11224b.htm

O'Hagan, Thomas
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11224c.htm

O'Hanlon, John
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11224d.htm

O'Hara, Theodore
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11224e.htm

Oklahoma
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11230c.htm

Olaf Haraldson, Saint
Martyr and King of Norway, d. 1030.
http://www.newadvent.org/cathen/11234a.htm

Olba
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11235a.htm

Old Catholics
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11235b.htm

Oldham, Hugh
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11239b.htm

Oldoini, Augustino
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11239c.htm

O'Leary, Arthur
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11240a.htm

Olenus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11240b.htm

Olesnicki, Zbigniew
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11240c.htm

Olinda
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11242a.htm

Oliva
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11242b.htm

Oliva, Gian Paolo
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11243a.htm

Olivaint, Pierre
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11243b.htm

Oliver, George
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11244a.htm

Olivi, Pierre Jean
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11245a.htm

Olivier de la Marche
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11246a.htm

Ollé-Laprune, Léon
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11246b.htm

Olmütz
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11247a.htm

Olympias, Saint
Widow, deaconess, renowned for her almsgiving, and a staunch supporter of St. John Chrysostom.
http://www.newadvent.org/cathen/11248b.htm

Ombus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11250a.htm

O'Meara, Kathleen
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11250b.htm

Omer, Saint
Swiss-born bishop of Terouenne in Belgic Gaul, founder of a monastery. He died in about 670.
http://www.newadvent.org/cathen/11251a.htm

Oporto
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11260a.htm

Oppenordt, Gilles-Marie
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11261a.htm

Oppido Mamertina
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11262a.htm

Optatus, Saint
Fairly long essay on the life and writings of this bishop, who argued against the Donatists. He died in about 387.
http://www.newadvent.org/cathen/11262b.htm

Orange, Councils of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11266b.htm

Orange Free State
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11267a.htm

Orange River, Vicariate Apostolic of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11268a.htm

Oratorio
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11270a.htm

Oratory
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11271a.htm

Orcagna
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11275b.htm

Orcistus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11276a.htm

Ordericus Vitalis
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11278a.htm

Ordinary
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11284b.htm

Ordines Romani
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11284c.htm

O'Reilly, Edmund (Theologian)
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11294a.htm

O'Reilly, Edmund (Archbishop of Armagh)
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11293c.htm

O'Reilly, Hugh
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11294b.htm

O'Reilly, John Boyle
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11294c.htm

O'Reilly, Myles William Patrick
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11294d.htm

Orense, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11295b.htm

Organ
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11297a.htm

Orientius
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11305b.htm

Origen and Origenism
Provides a biography and review of his works, as well as commentary on posthumous influences and the Origenistic Crises.
http://www.newadvent.org/cathen/11306b.htm

Oristano
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11316b.htm

Orkneys
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11316c.htm

Orlandini, Niccolò
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11317a.htm

Orléans, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11318b.htm

Orléans, Councils of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11318a.htm

Orley, Barent Van
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11320a.htm

Orme, Philibert de l'
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11321a.htm

Oropus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11321b.htm

O'Rorke, Patrick Henry
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11321c.htm

Orosius, Paulus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11322a.htm

Orphans and Orphanages
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11322b.htm

Orsi, Giuseppe Agostino
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11325a.htm

Orsini
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11325b.htm

Orsisius
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11328a.htm

Ortelius, Abraham
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11328b.htm

Orthodox Church
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11329a.htm

Orthodoxy
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11330a.htm

Orthodoxy, Feast of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11330b.htm

Orthosias
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11330c.htm

Ortolano Ferrarese
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11331a.htm

Orval
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11331b.htm

Orvieto
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11331c.htm

Ory, Matthieu
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11333a.htm

Osaka
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11333b.htm

Osbald
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11334b.htm

Osbern
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11335b.htm

Osee
The prophet and his book.
http://www.newadvent.org/cathen/11337a.htm

Osma, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11339a.htm

Osmund, Saint
A Norman by birth, Osmund became bishop of Salisbury, and died in 1099.
http://www.newadvent.org/cathen/11340a.htm

Ostia and Velletri
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11346a.htm

Oswald, Saint
Archbishop of York, d. 992 while washing the feet of the poor, as was his daily custom during Lent.
http://www.newadvent.org/cathen/11348b.htm

Othlo
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11350b.htm

Othmar, Saint
First abbot of St. Gall. He died in prison in 759.
http://www.newadvent.org/cathen/11351a.htm

Ottawa, Archdiocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11352a.htm

Ottawa, University of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11352b.htm

Otto, Saint
Swabian courtier, was named bishop of Bamberg in 1102, and founded over twenty monasteries.
http://www.newadvent.org/cathen/11353a.htm

Otto I (the Great)
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11354a.htm

Otto II
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11355a.htm

Otto III
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11356a.htm

Otto IV
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11357a.htm

Ottobeuren
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11358a.htm

Otto of Freising
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11358b.htm

Otto of Passau
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11359a.htm

Ouen, Saint
Seventh-century Archbishop of Rouen, founder of several monasteries, devoted to theological studies, friend of St. Eloi.
http://www.newadvent.org/cathen/11360b.htm

Overberg, Bernhard Heinrich
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11362b.htm

Oviedo, Diocese of
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11363a.htm

Oxenham, Henry Nutcombe
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11365a.htm

Oxford
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11365b.htm

Oxyrynchus
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11377a.htm

Ozanam, Jacques
(Catholic Encyclopedia)
http://www.newadvent.org/cathen/11378b.htm

Oliver Plunket, Saint
Biographical article on the professor of theology, Archbishop of Armagh and Primate of All Ireland, martyred in 1681.
http://www.newadvent.org/cathen/12169b.htm