Catholic Church
The Catholic Church, commonly known as the Roman Catholic Church, is the largest Christian denomination, with an estimated 1.27 to 1.41 billion baptized members worldwide as of 2025. One of the world's oldest continuously functioning institutions, it has played a formative role in the development of Western civilization. The Church consists of 24 sui iuris churches—the Latin Church and 23 Eastern Catholic Churches—which together encompass nearly 3,500 dioceses and eparchies governed by bishops. The pope, as bishop of Rome, serves as the Church's chief pastor.
Catholic doctrine is rooted in the Nicene Creed. The Church teaches that it is the "one, holy, catholic and apostolic Church" founded by Jesus Christ in the Great Commission; that its bishops are the successors of the apostles; and that the pope is the successor of Saint Peter, to whom Christ entrusted a unique pastoral role. It holds that the apostolic faith is transmitted through Scripture and sacred tradition, interpreted authentically by the magisterium, the Church's teaching authority. Catholic liturgical life includes the Roman Rite and other rites of the Latin Church, along with the diverse liturgical traditions of the Eastern Catholic Churches. Religious orders, monastic communities, third orders, and lay movements contribute to a wide range of theological and spiritual expressions within Catholicism.
Among the Church's seven sacraments, the Eucharist is regarded as the central act of worship 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 Queen of Heaven, and is honored through doctrines such as the Immaculate Conception, perpetual virginity, and Assumption, as well as through numerous devotional practices. Catholic social teaching emphasizes care for the poor, the sick, and the marginalized through the corporal and spiritual works of mercy. The Church operates tens of thousands of educational and medical institutions worldwide and is the largest non-governmental provider of education and health care. It also supports a wide array of charitable and humanitarian organizations.
The Catholic Church has exerted significant influence on Western philosophy, culture, art, literature, music, law, and science. Catholic communities are present worldwide through missions, migration, diaspora, and conversion, with a majority of Catholics now residing in the Global South—a demographic shift shaped by population growth in Africa, Asia, and Latin America and by secularization in parts of Europe and North America.
Relations between the Church and the Eastern Orthodox Church deteriorated gradually over many centuries. Although the mutual excommunications of 1054 are often cited as a symbolic turning point, modern scholarship views the definitive rupture as the result of a long process solidified by the Fourth Crusade, amid enduring theological, cultural, and political disputes, including disagreements over papal authority. Earlier separations occurred with the Church of the East after the Council of Ephesus and with the Oriental Orthodox Churches following the Council of Chalcedon, primarily over Christological controversies. The Eastern Catholic Churches—today numbering roughly 18 million members—comprise Eastern Christian communities that remained in or later entered communion with the pope under varying historical circumstances.
The Protestant Reformation of the 16th century led to the emergence of new Christian traditions and prompted the Catholic Counter-Reformation. Since the late 20th century, the Church has been the subject of sustained criticism concerning its teachings on sexuality, clerical celibacy, and abortion, as well as its prohibition of the ordination of women and its handling of cases of clerical sexual abuse.
The Diocese of Rome, governed directly by the pope, constitutes his local jurisdiction, while the Holy See—the See of Rome—serves as the central governing authority of the Catholic Church. Its administrative apparatus, the Roman Curia, is based in Vatican City, an independent city-state enclaved within Rome, where the pope is head of state and functions as an elective absolute monarch.
Name
Catholic 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" 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 Church." In the Catechetical Lectures 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, "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 and the Code of Canon Law. "Catholic Church" is also used in the documents of the Second Vatican Council, the First Vatican Council, the Council of Trent and numerous other official documents.
History
Apostolic era and papacy
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".
Antiquity and Roman Empire
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.In 313, Constantine the Great—the first Roman emperor to convert to Christianity—issued the Edict of Milan, which legalized the Christian faith, and he moved the imperial capital to Constantinople in 330. In 380, the Edict of Thessalonica made Nicene Christianity the state church of the Roman Empire, a status that continued within the shrinking territory of the Byzantine Empire until its fall in 1453. Elsewhere, the Church functioned independently of imperial authority, becoming especially evident after the East-West Schism. During the period of the Seven Ecumenical Councils, five principal sees emerged—Rome, Constantinople, Alexandria, Antioch, and Jerusalem—formalized in the mid-6th century, arranged by Justinian I, the Byzantine emperor from 527 to 565, as the pentarchy.
In 451, the Council of Chalcedon, in a canon of disputed validity, elevated the see of Constantinople to a role "second in eminence and power to the bishop of Rome". From, the bishops, or popes, of Rome steadily increased their authority through consistently intervening in helping orthodox leaders during theological disputes, which encouraged appeals to them. Emperor Justinian, under his controlled territories, established a form of caesaropapism where he could regulate "the minutest details of worship and discipline" and "theologian opinions" in the Church—establishing imperial influence over Rome and other Western territories again. This act created the Byzantine Papacy period in which popes required approval from the emperor or his representative for consecration, leading to most being selected by the emperor from his Greek-speaking subjects, which created a "melting pot" of Western and Eastern Christian traditions in art and liturgy.
In the following centuries, Germanic tribes who invaded the Roman Empire adopted Christianity in its Arian form, which the Council of Nicaea declared heretical, causing discord between Germanic rulers and Catholic subjects. In 497, Clovis I, the Frankish ruler, converted to orthodox Catholicism and he aligned himself with the papacy and the monastic communities—an act that unified Germanic rulers and Catholic subjects for the most part. Following his lead, the Visigoths converted to Catholicism in 589, and the Lombards in Italy gradually adopted it during the 7th century.
Western Christianity—particularly through its monastic institutions—played a massive role in preserving classical civilization, including its artistic traditions and literacy. Benedict of Nursia, one of the founders of Western monasticism, with his Rule, exerted a crucial influence on European culture with his appropriation of the Church's monastic spiritual heritage and his preservation and transmission of ancient culture with the spread of the Benedictine tradition. During this time, monastic Ireland became a center of scholarship; early Irish missionaries such as Columbanus and Columba spread Christianity and established monasteries across continental Europe.