Fabian, Pope and Martyr
Fabiola of Rome, Matron
Fabricio, Bishop of Porto, Portugal
Fabricius, Martyr
Facanan (Fachtna), First Bishop of Ross, Ireland
Facundus, Martyr
Faith (Foi), Virgin, Martyred at Agen, France
Famianus of Gallese (near Compostela) Cistercian Priest
Fanchea, Abbess of Rossory, Ireland
Faron, Bishop of Meaux
Fausta, Martyr
Fausta, Matron (Mother of St. Anastasia of Sirmium)
Fausta, Widow
Faustina Kowalska, Nun who experienced the Divine Mercy apparitions
Faustina, Martyr
Faustinus of Brescia, Priest and Martyr
Faustinus, Bishop of Bologna
Faustus, Bishop of Riez
Faustus, Martyr
Febadius, Bishop of Agen
Febronia of Nisibis, Virgin and Martyr
Felicia, Virgin, Martyred at Caligari, Sardinia
Felician of Rome, Martyr
Felicianus, Bishop of Foligno
Felicissima of Todi, Martyr
Felicissima of Valeria, Virgin and Martyr
Felicissimus, Martyr
Felicitas of Carthage
Felicitas, of Rome, Martyr and her seven martyred sons:
     Silanus
    Januarius
    Alexander
    Vitalis
    Martial
    Felix
    Philip
Felix I, Pope and Martyr
Felix III, Pope and Grandfather of Pope Gregory the Great
Felix Mary da Merola, Capuchin Priest
Felix of Cantalice, Capuchin Friar
Felix of Dunwich, First Bishop of East Anglia
Felix of Girona, Deacon and Martyr
Felix of Valois, Co-founder of the Theatines
Felix, Bishop and Martyr
Felix, Bishop of Nola
Felix, Martyr
Felix, Martyr
Ferbata of Seleucia, Widow, Sister of Simeon, Martyred by Sapur II of Persia
Ferdinand III, King of Castile
Ferdinand, Prince of Portugal
Ferinus, Martyr (I can find nothing about this saint)
Fermin, Bishop of Metz
Ferreol of Arles, Soldier and Martyr
Ferreol, Bishop of Limoges
Ferrutius (Ferruccio) of Mainz, Roman Soldier and Martyr
Fevronia (Febronia) Princess of Murom (Euphrosyne, her name in religion)
Fiacre, Hermit
Fidelis of Como, Soldier and Martyr
Fidelis of Sigmaringen, Capuchin Priest and Martyr
Fidelis, Bishop of Merida
Fidelis, Martyr
Fidentius, Martyr
Fidolus
Filarete (the Gardener) of Calabria, Basilian Abbot, successor to St. Elias of Enna
Filippo Ciardelli, Franciscan
Filippo Smaldone, Apostle of Our Lady of Pompeii, father of deaf, blind, and abandoned
Filon, Martyred in Nicomedia
Fingar (Guaire), Irish Missionary, Martyred in Cornwall
Finian of Clonard, Abbot
Finian of Moville, Abbot
Fintan, Abbot of Clonenagh
Firmatus, Martyr
Firmin, First Bishop of Amiens, Martyr
Firmus of Verona, Martyr
Flaminia, Virgin, Martyred in Nicomedia
Flannan, Bishop of Kilaloe, Ireland
Flavia, Martyr
Flavian, Martyr
Flavian, Patriarch of Constantinople
Flavius Clemens, Roman Senator, Uncle of Flavia Domitilla
Flora of Cordoba, Virgin and Martyr
Flora of Rome, Virgin and Martyr
Florentia, Martyr
Florentina of Cartagena, nun, Sister of Sts. Isidore, Leander, and Fulgentius
Florentius, Benedictine Confessor
Florentius, Bishop of Strassbourg
Florian, Soldier and Martyr
Floribert, son and successor to St. Hubert as Bishop of Liẻge
Florus of Arvernia in Aquitaine, Monk
Florus of Illyria, Stonemason, Martyr
Foillan (Folesinus), Irish Monk, Missionary, Martyr
Formundus, Bishop of Coutances
Fortunatus
Fortunatus, African Martyr
Fortunatus, Bishop of Naples
Fortunatus, Martyr
Forty Martyrs of Sebaste, Soldiers (one of them)
Foulques, Abbot of Fontenelle
Four Holy Crowned Ones, Martyrs, masons from Sirmium
     Castorius
     Claudius
     Nicostratus
     Symphorianus
Frances of Rome, Foundress of the Oblates of Mary (of Tor de’Specchi)
Frances Siedliska, Foundress of the Sisters of the Holy Family of Nazareth
Frances Xavier Cabrini, Foundress of the Missionary Sisters of the Sacred Heart, Died in Chicago’s Columbus Hospital on December 22, 1917, America’s First Saint
Francesco Pianzola, Priest, Founder of the Missionary Sisters of the Immaculate, Queen of Peace
Francis Aranha, Jesuit Lay Brother, Martyred in India
Francis Borgia, Jesuit Priest
Francis Caracciolo, Priest
Francis de Paula, Confessor, Founder of the Order of the Minims
Francis de Posadas, Dominican
Francis De Sales, Bishop of Geneva and Doctor of the Church
Francis Jerome (De Geronimo), Jesuit Priest
Francis Mary Croese of Camporosso, Capuchin Lay Brother
Francis Mary Paul Libermann, Second Founder of the Holy Spirit Order
Francis of Assisi, Deacon and Founder of the Franciscans
Francis Solano, Franciscan Missionary Priest
Francis Venimbene of Fabriano, Franciscan Priest, Disciple of St. Bonaventure
Francis Xavier Bianchi, Barnabite Priest, “Apostle to Naples”
Francis Xavier Can Nguyen, Vietnamese Catechist and Martyr
Francis Xavier Mau, Dominican Martyr of Viet Nam
Francis Xavier Seelos, Redemptorist Missionary to New Orleans
Francis Xavier, Jesuit Missionary Priest
Francis, Pope
Francisco Diaz de Ecija, Dominican Martyr of China
Francisco Espedito Lopes, 5th bishop of Garahuns, Brazil, martyr
Francisco Marto, Visionary of Fatima
Franco (Frank) Lippi, Carmelite Priest Mystic
Franco of Assergi, Benedictine Monk
Francois de Laval, Bishop of Quebec
Francoise Meziere de Mezanges, Laywoman, One of the 19 Martyrs of Laval, guillotined
Fraternus, Bishop of Auxerre
Fredegand, Irish Abbot of Deurne
Frederic Janssoone, Franciscan Priest
Frederic Ozanam, Founder of the St. Vincent de Paul Society
Frederick Feikone, Norbertine Abbot
Frederick, Bishop of Liege, Martyr
Frederick, Bishop of Utrecht, Martyr
Fredlemid (Phelim), Bishop of Kilmore
Fridolin, Irish Apostle to the Upper Rhein
Frigidian (Frediano), Irish Missionary, Bishop of Lucca
Fromundus, Bishop of Coutances
Fronto, Bishop of Perigeux
Fructuosus, Bishop of Braga
Fructuosus, Bishop of Terragona
Frumentius, Bishop of Ethiopia
Frutos (Fructus) of Segovia, Castilian Hermit, Martyr
Fugatius (Fagan), Roman Missionary to Britain
Fulbert, Bishop of Chartres
Fulcran, Bishop of Lodeve
Fulgentius, Bishop of Ruspe in Africa
Fulton John Sheen (Peter John Sheen), Archbishop of Rochester, New York
Fursey of Peronne, Irish Missionary to England and France
Fuscien (Fuscianus), Missionary Martyred near Amiens​