The Catholic Church (Latin: Ecclesia Catholica), also called the Roman Catholic Church, is the largest Christian church, with an estimated 1.28 to 1.41 billion baptized members worldwide as of 2026. It consists of 24 autonomous (sui iuris) churches—the Latin Church and 23 Eastern Catholic Churches—organized into nearly 3,500 dioceses and eparchies governed by bishops. Throughout history, the church has had a large role in the development of Western civilization. Catholic communities are present worldwide through missions, immigration, and conversions. The majority of Catholics live in the Global South, reflecting rapid demographic growth in Africa, Asia, and Latin America, as well as secularization in parts of Europe and North America.
Catholic doctrine is rooted in the Nicene Creed and holds that the church is the "one, holy, catholic and apostolic Church" founded by Jesus Christ. It teaches that bishops are the successors of the apostles and that the pope—the bishop of Rome—is the successor of Saint Peter the Apostle, entrusted with a unique and primary pastoral role. Leo XIV is the current pope, serving as the head of the church; the Diocese of Rome forms his local jurisdiction, while the Holy See serves as the church's central governing authority through the Roman Curia. Apostolic teaching is understood to be transmitted through Scripture and sacred tradition, interpreted by the magisterium, the church's teaching authority. Catholic liturgical life includes the Roman Rite, other rites of the Latin Church, and the liturgical traditions of the Eastern Catholic Churches. Religious orders, monastic communities, and lay movements contribute to a wide range of theological and devotional expressions within Catholicism globally.
Among the church's seven sacraments, the Eucharist is seen as the source and summit of the Christian life and is celebrated in the Mass. Catholics believe that through consecration by a priest, the bread and wine become the body and blood of Christ. The Virgin Mary is venerated as the Mother of God and honored through dogmas such as the Immaculate Conception, perpetual virginity, and Assumption, including devotional practices. Catholic social teaching emphasizes care for the poor, the sick, and the marginalized. The church operates tens of thousands of educational, medical, and charitable institutions worldwide, making it the largest non-governmental provider of education and health care.
Its relations with other Christian traditions have been shaped by divisions. The separation between the church and Eastern Orthodox churches within the state Roman church developed gradually and was solidified by the Fourth Crusade, amidst theological and political disputes, especially over papal authority. Earlier schisms occurred with the Church of the East after the Council of Ephesus (431) and with the Oriental Orthodox Churches following the Council of Chalcedon (451). The 16th century Protestant Reformation led to new Christian traditions and prompted the Catholic Counter‑Reformation. Since the late 20th century, the church has faced criticism on its teachings on sexuality, clerical celibacy, the ordination of women, and its handling of clerical sexual abuse.
Catholic (from Greek: καθολικός, romanized: katholikos, lit. 'universal') is first attested as an adjective used to describe the church in the early second century. The first known use of the phrase "the catholic church" (Greek: καθολικὴ ἐκκλησία, romanized: katholikḕ ekklēsía) appears in a letter written around AD 100 by Ignatius of Antioch to the Smyrnaeans, which reads: "Wheresoever the bishop shall appear, there let the people be, even as where Jesus may be, there is the universal [katholike] Church." In the Catechetical Lectures (c. 350) of Cyril of Jerusalem, the name "Catholic Church" was used to distinguish it from other groups that also called themselves "the church." The "Catholic" notion was further emphasized in the edict De fide catolica, issued in 380 by Theodosius I, the last emperor to rule over both the eastern and western halves of the Roman Empire, when he established the state church of the Roman Empire.
Since the East–West Schism of 1054, the Eastern Orthodox Church has taken the adjective "Orthodox" as its distinctive epithet; its official name continues to be the "Orthodox Catholic Church." The Latin Church was described as "Catholic", with that description also denoting those in communion with the Holy See after the Protestant Reformation of the 16th century, when those who ceased to be in communion became known as Protestants.
While the "Roman Church" has been used to describe the pope's Diocese of Rome since the Fall of the Western Roman Empire and into the Early Middle Ages (6th–10th century), "Roman Catholic Church" has been applied to the whole church in the English language since the Protestant Reformation in the late 16th century. Further, some refer to the Latin Church as "Roman Catholic" in distinction from the Eastern Catholic churches. "Roman Catholic" has occasionally appeared in documents produced by the Holy See, and has been used by certain national episcopal conferences and local dioceses.
The name "Catholic Church" for the whole church is used in the Catechism of the Catholic Church (1990) and the Code of Canon Law (1983). "Catholic Church" is also used in the documents of the Second Vatican Council (1962–1965), the First Vatican Council (1869–1870), the Council of Trent (1545–1563) and numerous other official documents.
The New Testament, particularly the Gospels, records Jesus' activities and teaching, his appointment of the Twelve Apostles, and his Great Commission to them, instructing them to continue his work. The Acts of Apostles recounts the founding of the Christian Church and the spread of its message throughout the Roman Empire. The Catholic Church teaches that its public ministry began on Pentecost, which occurred fifty days after the date on which Christ is believed to have risen from the dead. At Pentecost, the apostles are held to have received the Holy Spirit, preparing them for their mission of leading the church. The Catholic Church further teaches that the college of bishops, led by the bishop of Rome, is the successor to the apostles.
In the account of the Confession of Peter found in the Gospel of Matthew, Christ designates Peter as the "rock" upon which his Church will be built. The Catholic Church considers the bishop of Rome, the pope, to be the successor of Saint Peter. Some scholars hold that Peter was the first bishop of Rome, while other scholars argue that the institution of the papacy does not depend on the view that Peter was bishop of Rome, or even on the claim that he ever resided in Rome.
Many scholars maintain that a church structure consisting of multiple presbyters/bishops persisted in Rome until the mid-2nd century, when a structure with a single bishop and multiple presbyters was adopted, and that later writers retrospectively applied the title "bishop of Rome" to the most prominent members of the clergy in the earlier period, as well as to Peter himself. On this basis, Bart D. Ehrman argues Peter "could not have been the first bishop of Rome", while also noting that the church "did not have anyone as its bishop until about a hundred years after Peter's death." Raymond E. Brown likewise states that it is anachronistic to speak of Peter in terms of a local bishop of Rome, but that Christians of that period would have regarded Peter as exercising roles that contributed "to the development of the role of the papacy in the subsequent church." These roles, Brown argues, "contributed enormously to seeing the bishop of Rome ... as the successor of Peter ... for the church universal."
The Roman Empire facilitated the spread of new ideas through its extensive network of roads and waterways, the relative security of the Pax Romana, and the promotion of a common culture with strong Greek influences, all of which allowed ideas to be more easily expressed and understood. However, unlike most religions in the Roman Empire, Christianity required its followers to renounce all other gods, a practice inherited from Judaism. Because Christians refused to participate in pagan festivals and civic rituals, they were excluded from many aspects of public life, leading some non-Christians, including government authorities, to fear that they were angering the gods and thereby threatening the peace and prosperity of the empire. The resulting prosecutions became a defining element of early Christian self-understanding until Christianity was legalized in the 4th century.