An Episcopalian-born American Catholic convert, educator, and pioneer, she established the first Catholic girls' school in the U.S., founded the Sisters of Charity, and was canonized as the first native-born American saint, inspiring others through her charitable works and dedication to education.

Born into wealth, he chose a life of poverty and spirituality, founded the Franciscan Order, advocated vows of poverty, chastity, and obedience, and is celebrated for his stigmata, Canticle of the Sun, Christian mysticism, and as the patron saint of animals and the environment.

A revered bishop and miracle worker from ancient Anatolia, known for saving three sisters from destitution and preventing the execution of three innocent men, inspired the beloved figure of Santa Claus through his secret gift-giving practices, becoming a cherished saint in Christian tradition worldwide.

A revered desert ascetic, known as the "Father of Monasticism," retreated to the Egyptian desert, overcoming intense spiritual struggles and demonic visions, inspiring many to pursue monastic lives and laying the foundation for Christian monasticism.

A renowned physician in Emperor Maximian's court, he converted to Christianity, performed miraculous healings, and was martyred during the Diocletian persecution, later becoming one of the Fourteen Holy Helpers in the Catholic Church.

Monastic founder who penned the influential "Basilian Rule," defended Nicene Christianity as Bishop of Caesarea and is celebrated for founding charitable institutions like a renowned hospital, emphasizing Christian charity and care.

• Mohawk-Algonquin Convert: Overcame smallpox and family loss to embrace Catholicism at age 19.
• Devout Ascetic: Practiced severe penances and vowed perpetual virginity, inspiring fellow converts.
• First Native American Saint: Canonized in 2012; patroness of ecology and Indigenous peoples.

Originating from Antioch, a renowned orator earned the title "golden-mouthed," faced challenges as Archbishop of Constantinople due to his teachings on virtue and wealth, and despite multiple exiles, his writings profoundly influenced Christian theology, establishing him as a revered Church Father.

A Roman soldier of Greek origin, renowned for his unwavering Christian faith and bravery, was executed during Emperor Diocletian's persecutions, is famed for the legendary dragon-slaying tale symbolizing triumph over evil, and is venerated widely as a patron saint of numerous countries and causes.

Despite facing exile and brutal punishments for ardently opposing Monothelitism and defending Christ's dual wills, his profound theological writings and teachings profoundly influenced Christian dogma, solidifying his status as a pivotal Church Father.

A deacon and prolific hymn writer, used poetry to combat heresies, lived an ascetic life in Nisibis and Edessa, founded a theological school, and is revered for his theological writings, earning him the title of Doctor of the Church.

A Cappadocian Father eloquently defending the Trinity against Arianism, he faced theological and political strife as Patriarch of Constantinople, with his enduring orations and poetic writings solidifying his reputation as a key architect of Trinitarian doctrine.

• Dominican Friar and Theologian:  authored the Summa Theologica, blending Aristotle’s philosophy with Christian doctrine.
• Influential Thinker:  writings shaped Western philosophy, education, and the Catholic Church for centuries.
• Canonized Saint: experienced mystical visions that strengthened his faith and was honored for his scholarship and piety.

A Christian soldier martyred for his faith, later attributed with numerous miracles and honored as a Great Martyr, became the patron saint of Thessaloniki, with his relics a pilgrimage site and annual commemoration in Eastern Orthodox traditions.

A noblewoman converted to Christianity after a vision, became a scholar and debater, challenged the Roman Emperor, converted 50 pagan philosophers, was martyred by wheel torture, and is now revered as a Christian saint and one of the Fourteen Holy Helpers.

Twin brothers known as "moneyless healers" for providing free medical services were martyred in Asia Minor during the Diocletian persecution and are revered as patron saints of physicians and surgeons, celebrated for their sanctity and post-mortem miracles.

An Eastern Christian monk known for his spiritual writings on inner prayer, asceticism, and God's love, he briefly served as Bishop of Nineveh before resigning to monastic life, with his ascetical homilies profoundly influencing both Eastern and Western Christian mysticism and monastic spirituality.

A passionate defender of Christ's divinity, this bishop's role at the Council of Nicaea and his theological works, notably "On the Incarnation," profoundly shaped Christian doctrine, despite facing multiple exiles and challenges.

• Carmelite Nun and Mystic: Entered the Lisieux convent at 15, embracing a life of contemplative prayer.
• Advocate of the 'Little Way': Promoted seeking holiness through small, everyday acts of love and humility.
• Doctor of the Church: Canonized in 1925; declared a Doctor in 1997 for profound spiritual writings.

A former court official who became a monk, he defended icon veneration against Iconoclasts and authored influential theological works, including the "Exposition of the Orthodox Faith," earning him recognition as a "Doctor of the Church."

A pivotal theologian, as Patriarch, vigorously defended the doctrine of Christ as fully God and fully man against Nestorianism, played a central role in the 431 AD Council of Ephesus ensuring the title Theotokos for the Virgin Mary, and profoundly shaped Christological teachings through his theological writings and pastoral letters, earning recognition as a Doctor of the Church.

After a decade of licentiousness in Alexandria, she experienced a profound conversion at Jerusalem's Church of the Holy Sepulchre, leading her to live as a hermit in the Jordanian desert for 47 years, embodying penance and becoming a symbol of repentance in Christian tradition.

A noblewoman secretly converted to Christianity, honored the Holy Trinity with three tower windows, faced brutal tortures and beheading by her father, and is now revered as a protector against lightning and explosions, becoming the patron saint of artillerymen, miners, and others working with explosives.