World Religions

Scholars generally describe religion as a system of shared beliefs, practices, ethical commitments, and community life organized around what adherents regard as sacred or transcendent. Religions are not only about abstract ideas; they also shape daily rhythms, life-cycle rituals, legal codes, art, music, architecture, and the way communities respond to birth, illness, suffering, and death. Because religious traditions have interacted with politics, migration, trade, and colonial history for millennia, their present-day distribution reflects long and often complicated historical processes.

There is no single authoritative count of the world's religions. Researchers recognize thousands of distinct traditions, though a relatively small number have global reach. The Pew Research Center and the Gordon-Conwell Center for the Study of Global Christianity publish regular estimates of adherents by tradition and region. According to these widely cited sources, as of the mid-2020s approximate global figures are: Christianity around 2.4 billion adherents, Islam around 2 billion, Hinduism around 1.2 billion, Buddhism between 500 and 535 million, folk and ethnic religions over 400 million, Sikhism between 25 and 30 million, and Judaism around 15 million. The religiously unaffiliated, sometimes called "nones," number approximately 1.2 billion. Specific figures shift from year to year and vary between surveys; readers are encouraged to consult primary sources for current data.

Geographic distribution is highly uneven. Christianity is the most globally dispersed tradition, with large communities on every inhabited continent. Islam spans a broad arc from North Africa through the Middle East, South Asia, and into Southeast Asia, with the largest Muslim-majority country being Indonesia. Hinduism is concentrated in India and Nepal, with substantial diaspora communities. Buddhism is rooted in South, Southeast, and East Asia. Judaism is concentrated in Israel and the United States. The unaffiliated are most numerous in East Asia, especially in China, and in parts of Europe.

This page introduces each major tradition on its own terms, using widely accepted scholarly descriptions. It does not make claims about religious truth and does not advocate for any tradition. Dedicated child pages provide deeper treatment of each religion, and country profiles explore religious demographics in national context.

Defining religion is itself a subject of scholarly debate. Substantive definitions focus on content, such as belief in gods, spirits, or a sacred realm. Functional definitions focus on what religion does in a community, such as providing shared meaning, ethical orientation, collective identity, or frameworks for ritual and life-cycle observance. Neither approach captures every tradition cleanly. Some traditions center on a personal creator deity, others on impersonal cosmic principles, and still others on ancestral spirits and the sacredness of particular landscapes. The category of religion itself emerged primarily from Western academic scholarship and has been critiqued for fitting some traditions better than others.

One common scholarly approach groups traditions into broad families. The Abrahamic family, tracing shared origins to the patriarch Abraham, includes Judaism, Christianity, and Islam, and is distinguished by monotheism and scriptural authority. The Dharmic family, rooted in the Indian subcontinent, includes Hinduism, Buddhism, Jainism, and Sikhism, which share concepts such as dharma, karma, and rebirth while differing on many points of belief. East Asian traditions include Confucianism, Taoism, and Shintō, often practiced alongside Buddhism in syncretic combinations. Indigenous and folk religions encompass thousands of distinct traditions rooted in specific peoples and places, including Yoruba and other West African religions, the African diaspora religions of the Americas, Native American traditions, Aboriginal Australian Dreamings, Siberian and Arctic practices, and pre-Christian European traditions and their contemporary revivals. These families are useful orienting categories rather than rigid boundaries; real-world practice frequently crosses them.

Christianity is the largest religious tradition in the world, with approximately 2.4 billion adherents according to the Pew Research Center and the Gordon-Conwell Center for the Study of Global Christianity. It emerged in the first century of the Common Era from Jewish origins in the Roman province of Judea, centered on the life, teachings, death, and, according to Christian belief, resurrection of Jesus of Nazareth, whom Christians regard as the Messiah and Son of God. Its canonical scripture is the Bible, comprising the Old Testament, shared in large part with Judaism, and the New Testament, which includes the four Gospels, the Acts of the Apostles, epistles attributed to early Christian leaders, and the Book of Revelation.

Christianity spread through missionary activity, empire, migration, and conversion across two millennia and is today the most geographically dispersed world religion. It is the majority tradition in Europe, the Americas, Sub-Saharan Africa, and much of Oceania, with growing communities in parts of Asia. Brazil has the largest Roman Catholic population of any country. The sections below describe the major Christian families, each of which contains its own internal variety of liturgy, governance, and theological expression.

The Roman Catholic Church

The Roman Catholic Church is the largest single Christian body in the world, with approximately 1.3 to 1.4 billion baptized members according to the Pontifical Yearbook published annually by the Holy See. It traces its origin to Jesus and the apostles, and it regards the Bishop of Rome, known as the Pope, as the successor of the apostle Peter and the visible head of the universal church. The headquarters of the Catholic Church is the Vatican City State, an independent city-state enclaved within Rome, Italy. The reigning pope, Pope Leo XIV, was elected in 2025 as the first United States-born pontiff in history.

Catholic theology centers on the celebration of the seven sacraments — baptism, confirmation, the Eucharist, reconciliation (confession), the anointing of the sick, marriage, and holy orders — through which the faithful are understood to receive divine grace. The Eucharistic celebration, known as the Mass, is the central act of Catholic worship. Catholic doctrine emphasizes the unity of Scripture and sacred Tradition, the intercession of the Virgin Mary and the saints, and the authority of the magisterium, the church's formal teaching office. Liturgical life follows a calendar structured around Advent, Christmas, Lent, Easter, and Ordinary Time, with feast days commemorating saints and central mysteries of the faith.

The Catholic Church is organized into dioceses led by bishops, with parishes headed by priests. Beyond the Latin Church, which uses the Roman Rite and is by far the largest, the Catholic Church includes twenty-three Eastern Catholic churches — among them the Maronite, Melkite, Ukrainian Greek Catholic, Syro-Malabar, and Chaldean Catholic churches — that preserve ancient Eastern liturgical, theological, and canonical traditions while remaining in full communion with Rome. Religious orders such as the Benedictines, Franciscans, Dominicans, Jesuits, and Carmelites have shaped Catholic life through teaching, preaching, scholarship, contemplation, and service. The Second Vatican Council (1962-1965) substantially renewed liturgy, pastoral practice, and relations with other Christian communions and world religions.

Catholicism is the majority tradition across Latin America, Southern Europe, the Philippines, and much of Sub-Saharan Africa, where growth has been rapid in recent decades. Brazil, Mexico, the Philippines, the United States, and Italy contain the five largest national Catholic populations. The Holy See maintains diplomatic relations with more than 180 states.

Eastern Orthodoxy

Eastern Orthodoxy, with approximately 220 million adherents, is the second-largest family within global Christianity. It is organized not as a single centralized body but as a communion of autocephalous (self-governing) churches in sacramental and doctrinal unity. The Ecumenical Patriarch of Constantinople is recognized as first among equals (primus inter pares), holding a position of honor rather than jurisdictional authority over other churches. Major autocephalous bodies include the Patriarchates of Constantinople, Alexandria, Antioch, and Jerusalem, together with the Russian, Serbian, Romanian, Bulgarian, Georgian, and Greek Orthodox churches, and several additional national and regional jurisdictions.

Eastern Orthodoxy separated from Rome in the Great Schism of 1054, a division that accumulated over centuries through disagreements on the authority of the papacy, the Filioque clause added to the Nicene Creed in the Western church, and differences in liturgy and discipline. Orthodox worship preserves the Divine Liturgy, most commonly that of Saint John Chrysostom, richly chanted liturgies, the extensive veneration of icons, monasticism with its great center at Mount Athos in Greece, and a robust ascetic and mystical theology often associated with the hesychast tradition. Russia, Ukraine, Romania, Greece, and Serbia contain large Orthodox populations.

Oriental Orthodoxy and the Assyrian Church

Oriental Orthodoxy is a communion of ancient churches that parted from the rest of Christianity following the Council of Chalcedon in 451, in disputes over the formulation of the two natures of Christ. These churches reject the Chalcedonian definition on technical terms while affirming the orthodoxy of their own Christological teaching. The Oriental Orthodox family includes the Coptic Orthodox Church of Alexandria (Egypt), the Ethiopian Orthodox Tewahedo Church (Ethiopia), the Eritrean Orthodox Tewahedo Church, the Armenian Apostolic Church (Armenia), the Syriac Orthodox Church, and the Malankara Orthodox Syrian Church of India, together numbering roughly 60 million adherents.

The separately organized Assyrian Church of the East, historically rooted in the Church of the East that spread across Persia and Central Asia along the Silk Road, is sometimes discussed alongside Oriental Orthodoxy though its Christological tradition differs. Ongoing ecumenical dialogue in the twentieth and twenty-first centuries has substantially narrowed historic disagreements among Chalcedonian, Oriental Orthodox, and Assyrian traditions.

Protestantism

Protestantism emerged in the sixteenth century in a series of reform movements within Western Christianity, most notably the Lutheran Reformation initiated by Martin Luther in 1517, the Swiss and later international Reformed movement associated with Ulrich Zwingli and John Calvin, the English Reformation, and the Radical Reformation of the Anabaptists. Common Protestant commitments historically include the authority of Scripture (sola scriptura), justification by grace through faith, and the priesthood of all believers. Protestantism now numbers between 800 and 900 million adherents worldwide across thousands of denominations and independent congregations.

Major Protestant families include the Lutheran churches, centered historically in Germany and the Nordic countries and strong today in parts of Sub-Saharan Africa, particularly Ethiopia and Tanzania. The Reformed and Presbyterian family, including churches shaped by Calvin and John Knox, is strong in South Korea, the Netherlands, parts of Switzerland, Scotland, and South Africa. The Anglican Communion, centered on the See of Canterbury, includes the Church of England, the Episcopal Church in the United States, and national churches across the United Kingdom's former imperial reach, with 85 million members concentrated today in Nigeria, Uganda, Kenya, and other African nations. Baptist churches, emphasizing believer's baptism and congregational governance, include the Southern Baptist Convention as the largest single Protestant body in the United States. Methodist churches, rooted in the eighteenth-century revival led by John Wesley, remain influential in the United Kingdom, the United States, Nigeria, and across Africa. Pentecostal and Charismatic movements, which emerged in the early twentieth century and emphasize the gifts of the Holy Spirit, have grown with extraordinary speed in the Global South; Assemblies of God, Church of God in Christ, and the many independent Pentecostal and neo-Pentecostal networks now represent one of the fastest-expanding segments of world Christianity, with major centers in Brazil, Nigeria, South Korea, and Guatemala.

Additional Protestant and Protestant-adjacent communities include the Evangelical and non-denominational churches that now form a large share of United States Christianity; the Holiness and Wesleyan traditions (Church of the Nazarene, Salvation Army, Wesleyan Church); the Anabaptist descendants (Mennonite, Amish, Brethren); Quakers (Religious Society of Friends); Seventh-day Adventists; and the Churches of Christ. The African Independent (or Initiated) Churches, such as the Zion Christian Church in South Africa and numerous Aladura churches in West Africa, represent indigenous African Christianity that blends Protestant inheritance with distinct African forms of worship and leadership.

The Church of Jesus Christ of Latter-day Saints

The Church of Jesus Christ of Latter-day Saints, historically known as the Mormon church, understands itself as the restored church of Jesus Christ in the modern age. Members are called Latter-day Saints or, in common usage, Mormons. The Church teaches that Jesus Christ is the central figure of its doctrine and practice, that God is a loving Heavenly Father who knows and guides his children individually, and that through continuing revelation to modern prophets the fullness of the gospel has been restored to the earth. Global membership stands at approximately seventeen million, with the largest populations in the United States, Mexico, Brazil, the Philippines, and across Central America, the Pacific, and parts of West Africa.

The Church traces its history to events in upstate New York in the early nineteenth century. In 1820, a fourteen-year-old farm boy named Joseph Smith experienced the First Vision, in which God the Father and Jesus Christ appeared to him in a grove of trees near his family home in Palmyra. In the years that followed, Joseph Smith received further revelations, including the visit of an angelic messenger named Moroni, who directed him to a set of ancient inscribed gold plates buried in a hillside. Joseph Smith translated the plates into English by the gift and power of God, and the resulting text was published in 1830 as the Book of Mormon. On April 6 of that same year, the Church was formally organized in Fayette, New York, with Joseph Smith as its first president and prophet. Early congregations moved westward across the United States under pressure of persecution, first to Kirtland, Ohio, then Missouri, and then to Nauvoo, Illinois, where Joseph Smith was killed by a mob in 1844. Under the leadership of the next prophet, Brigham Young, the body of the Church migrated across the Great Plains and the Rocky Mountains, arriving in the Salt Lake Valley of present-day Utah in July 1847. Salt Lake City has remained the worldwide headquarters of the Church ever since.

The Book of Mormon is the foundational scripture of the Latter-day Saint gospel, and the Church holds it up as another testament of Jesus Christ alongside the Bible. The text is a record of ancient prophets and inhabitants who lived in the Americas from about 600 before the Common Era through the fourth century of the Common Era, and it culminates in a recorded ministry of the resurrected Jesus Christ among those peoples. Latter-day Saints affirm the Bible, including both the Old Testament and the New Testament, as the word of God, and they read the Book of Mormon alongside it as a witness of the same Savior. Together with two additional books of revealed scripture, the Doctrine and Covenants (which records modern revelations given to Joseph Smith and later Church presidents) and the Pearl of Great Price (which contains further inspired translations and writings), these four books make up the standard works of Latter-day Saint scripture. The Church teaches that its canon remains open in principle because God continues to reveal his will through living prophets and apostles.

Temples occupy a central and distinctive place in Latter-day Saint practice. The Church describes its temples as its most sacred buildings, set apart from ordinary meetinghouses and reserved for holy ordinances. In weekly Sunday worship, members gather at local chapels for sacrament services and instruction; in temples, by contrast, members who have made appropriate preparation enter to make and renew covenants with God, to receive the endowment (a course of sacred instruction and promise), and to participate in sealing ordinances that, according to Latter-day Saint belief, bind husband to wife and parents to children for eternity rather than only for this life. Latter-day Saints also perform vicarious ordinances on behalf of deceased ancestors, which motivates the Church's extensive genealogical and family-history work administered through FamilySearch. The number of operating temples worldwide has grown rapidly in recent decades; over two hundred are in operation across six continents with new temples being built on an annual basis.

The Church is led by a President, sustained by members as a prophet, seer, and revelator, who serves together with two counselors in what is called the First Presidency; a Quorum of Twelve Apostles; and additional Quorums of the Seventy that help administer Church affairs regionally. Congregations around the world are organized into geographic units called wards and branches, which are grouped into stakes and districts. The priesthood is held by worthy lay men, who serve without professional salary, and women serve in substantial leadership callings across the auxiliary organizations of Relief Society, Young Women, and Primary. The Church's missionary program, in which young men, young women, and senior couples volunteer to teach the gospel full-time for periods of one and a half to two years, is among the largest volunteer religious missionary efforts in the world; more than 70,000 missionaries serve at any given time. Other recognizable features of Latter-day Saint life include the Word of Wisdom, a code of health that counsels against alcohol, tobacco, coffee, tea, and the misuse of drugs; the practice of tithing; the Welfare Program and extensive humanitarian aid administered through Latter-day Saint Charities; and the Church-owned university system anchored by Brigham Young University in Provo, Utah.

Islam is the second-largest religion in the world, with approximately 2 billion adherents according to recent Pew Research Center estimates. It emerged in the seventh century of the Common Era in the Arabian Peninsula through the prophethood of Muhammad, whom Muslims regard as the final prophet in a line that includes figures also recognized in Judaism and Christianity, such as Abraham, Moses, and Jesus. The central scripture of Islam is the Qur'an, which Muslims believe to be the direct word of God revealed to Muhammad. The Qur'an is supplemented by hadith, reports of the sayings and actions of Muhammad, and by a substantial tradition of Islamic jurisprudence known as fiqh.

Islam has two principal branches. Sunni Islam, which represents roughly 85 to 90 percent of Muslims worldwide, developed from those who accepted the early caliphate and the consensus of the Muslim community on legal and theological matters. Shi'a Islam, representing approximately 10 to 15 percent, traces its distinctive identity to support for the leadership of Ali ibn Abi Talib and his descendants. Within these main branches are numerous subdivisions, including Twelver, Ismaili, and Zaidi Shi'a traditions, and the distinct Ibadi community based in Oman. The Alawite and Druze communities share some Islamic roots, though classification varies. Sufism, the mystical dimension of Islam, is present across branches.

Core devotional life is organized around the Five Pillars: the declaration of faith (shahada), daily ritual prayer (salah), almsgiving (zakat), fasting during the month of Ramadan (sawm), and pilgrimage to Mecca (hajj) for those physically and financially able. The largest Muslim-majority populations are in Indonesia, Pakistan, India, Bangladesh, Egypt, Nigeria, Iran, and Turkey. Mecca and Medina, in Saudi Arabia, are the two holiest cities of Islam. For deeper treatment, see the Islam landing page.

Hinduism is often described by scholars as the world's oldest continuously practiced major religious tradition. Its roots draw from the Indus Valley civilization and the Vedic religion of the ancient Indo-Aryan peoples, with widely cited chronological markers in the second and first millennia before the Common Era. Unlike the Abrahamic traditions, Hinduism has no single founder, no single authoritative text, and no centralized religious hierarchy. Its primary textual corpus includes the Vedas, the Upanishads, the epics Ramayana and Mahabharata, the Bhagavad Gita, the Puranas, and a vast body of devotional and philosophical literature.

Contemporary Hinduism is better understood as a family of related traditions than as a single uniform system. Major streams include Vaishnavism, which centers devotion on Vishnu and his avatars such as Rama and Krishna; Shaivism, which centers devotion on Shiva; Shaktism, which centers devotion on the Goddess in her many forms; and Smartism, a tradition associated with domestic worship of multiple principal deities. Philosophical schools range from strict nondualism (Advaita Vedanta) to qualified nondualism and dualism. Yoga, in both its physical and contemplative forms, is rooted in Hindu tradition.

Core concepts widely shared across Hindu traditions include dharma, understood as ethical duty and cosmic order; karma, the principle that actions have moral consequences across lifetimes; samsara, the cycle of rebirth; and moksha, liberation from that cycle. Hinduism is predominantly practiced in India and Nepal, with significant diaspora communities in Mauritius, Trinidad and Tobago, Guyana, Sri Lanka, United Kingdom, United States, Canada, and several Southeast Asian countries. For deeper treatment, see the Hinduism landing page.

Buddhism emerged in the fifth century before the Common Era in the northeastern Indian subcontinent, in what is today Nepal and India. It is founded on the teachings of Siddhartha Gautama, known as the Buddha, whose biographical details are preserved and elaborated across centuries of tradition. Global adherence is widely estimated between 500 and 535 million, according to the Pew Research Center and Gordon-Conwell Center for the Study of Global Christianity figures, though counts are complicated in East Asian contexts where Buddhism is often practiced alongside other traditions.

Core teachings include the Four Noble Truths, which diagnose the nature of suffering and its cessation, and the Noble Eightfold Path, which sets out an ethical, contemplative, and wisdom-based discipline for reaching liberation. Central concepts include impermanence (anicca), non-self (anatta), and dependent origination (pratityasamutpada). Monasticism is a historically important institution in most Buddhist traditions, and meditation practice in its many forms is widely regarded as a distinctive feature of the path.

Three principal branches are conventionally recognized. Theravada Buddhism, sometimes described as closer in form to early monastic Buddhism, predominates in Thailand, Sri Lanka, Myanmar, Cambodia, and Laos. Mahayana Buddhism, which emphasizes the bodhisattva ideal and a broad range of sutras beyond the early corpus, predominates in China, Japan, South Korea, and Vietnam. Vajrayana Buddhism, which incorporates tantric practices, is historically rooted in Bhutan, Mongolia, and the Himalayan regions, including Tibetan communities. For deeper treatment, see the Buddhism landing page.

Judaism is the oldest of the Abrahamic religions and one of the oldest continuously practiced monotheistic traditions in the world. Jewish tradition traces its beginnings to the covenant between God and Abraham, conventionally dated to the early second millennium before the Common Era, and to the Mosaic revelation at Sinai in the thirteenth century before the Common Era, though historians discuss these figures and events in a range of scholarly frameworks. Global adherence is approximately 15 million, with the largest communities in Israel and the United States, and smaller but historically significant communities in France, Canada, the United Kingdom, Argentina, and elsewhere.

The central scripture of Judaism is the Hebrew Bible (Tanakh), whose first section, the Torah, contains the Five Books of Moses. Rabbinic Judaism elaborates a substantial tradition of oral Torah preserved in the Mishnah and the two Talmuds (Jerusalem and Babylonian), along with extensive later legal codes and commentaries. Jewish theology centers on the oneness of God, the covenant with the Jewish people, ethical responsibility (mitzvot), and the study of sacred text.

Contemporary Judaism includes several major movements. Orthodox Judaism emphasizes continuity with traditional halakhic observance and includes Modern Orthodox and Haredi communities, among them Hasidic groups. Conservative (Masorti) Judaism seeks to balance traditional practice with historical scholarship. Reform and Reconstructionist Judaism emphasize ethical principles and adaptive practice. Additional branches include Renewal, Humanistic, and various Sephardic and Mizrahi communities whose liturgical and cultural traditions predate the Ashkenazi-centered modern movements. Key observances include the weekly Shabbat, the High Holy Days of Rosh Hashanah and Yom Kippur, the pilgrimage festivals of Passover, Shavuot, and Sukkot, and commemorations such as Hanukkah and Purim. For deeper treatment, see the Judaism landing page.

Sikhism originated in the Punjab region of South Asia in the late fifteenth century through the teachings of Guru Nanak (1469–1539) and developed through a succession of nine further Gurus concluding with Guru Gobind Singh (1666–1708). With approximately 25 to 30 million adherents worldwide, Sikhism is one of the largest religions that is distinct in origin from the Abrahamic and classical Dharmic families, though it shares a South Asian context with Hinduism and Islam. The central scripture is the Guru Granth Sahib, regarded by Sikhs as the eternal Guru and containing hymns by the Sikh Gurus along with compositions by Hindu and Muslim saints.

Core Sikh teachings include the oneness of God (Ik Onkar), the equality of all human beings regardless of caste, gender, or creed, the importance of selfless service (seva), honest work, and the remembrance of God's name. Initiated Sikhs (Khalsa) observe the Five Ks: kesh (uncut hair), kara (a steel bracelet), kanga (a wooden comb), kachera (cotton undergarments), and kirpan (a ceremonial sword). The community-kitchen tradition (langar), offering free meals to all visitors regardless of background, is a defining institution of Sikh gurdwaras. The majority of Sikhs live in India, particularly the state of Punjab, with sizable diaspora communities in Canada, the United Kingdom, the United States, Australia, and the Gulf states. For deeper treatment, see the Sikhism landing page.

Several influential East Asian traditions are sometimes classified as religions, sometimes as philosophies or ethical systems, and sometimes as cultural frameworks. The distinction is contested, and many East Asian people participate in elements of more than one tradition alongside Buddhism and local folk religion. Scholars generally agree that separating religion, philosophy, and culture in these contexts reflects Western categories more than it reflects lived practice.

Confucianism derives from the teachings of Confucius (Kongzi, 551–479 before the Common Era) and their elaboration by later thinkers such as Mencius and Xunzi. It emphasizes ethical cultivation, filial piety, ritual propriety, benevolence, and social harmony, and it has shaped government, education, and family life across China, Korea, Japan, and Vietnam for more than two millennia. Taoism (Daoism) is a Chinese tradition that centers on the Dao, or Way, and on cultivating alignment with its spontaneous patterns. Attributed key texts include the Daodejing, associated with Laozi, and the Zhuangzi. Taoism developed both philosophical and organized religious forms, with priesthoods, liturgies, and temples.

Shintō is the indigenous religious tradition of Japan, centered on the veneration of kami, the sacred presences associated with natural features, ancestors, and particular shrines. Shintō practice emphasizes purity, seasonal festivals, and rites of passage, and it coexists with Buddhism across the Japanese religious landscape. Together these traditions continue to influence ritual, ethics, and public life across East Asia, and they are often practiced in combination with folk religion and ancestor veneration rather than as exclusive identities.

Folk and indigenous religions are not a single tradition but a broad scholarly category covering thousands of distinct practices rooted in specific peoples, places, and ancestral lineages. The Pew Research Center estimates that over 400 million people identify primarily with a folk or ethnic religion, with many more practicing such traditions alongside a world religion such as Buddhism or Christianity. Many of these traditions are oral, ritual, and place-based rather than scriptural, though some have developed written corpora over time.

Representative examples include traditional African religions such as those of the Yoruba, Akan, Igbo, and Zulu peoples, in which ancestors, nature spirits, and a supreme creator are often key figures. African diaspora religions, shaped by the forced migration of the Atlantic slave trade and the blending of African, European, and Indigenous American elements, include Vodou in Haiti, Candomblé in Brazil, and Santería in Cuba and its diaspora. Indigenous traditions of the Americas range widely across nations and language groups, as do Aboriginal Australian traditions centered on the concept of the Dreaming. Siberian and Arctic traditions are often associated with shamanic practices. Pre-Christian European traditions, largely discontinued during medieval Christianization, have been the subject of modern reconstructions and revivalist movements such as Ásatrú and various forms of contemporary paganism.

Common features identified by scholars include animism, the attribution of spiritual presence to beings and features of the natural world; ancestor veneration; ritual specialists such as shamans, priests, or diviners; and a strong tie between religious practice and specific landscapes. These traditions frequently intersect with concerns about cultural survival, land rights, and the protection of sacred sites, and they are increasingly studied on their own terms rather than through frameworks designed for scriptural world religions.

The religiously unaffiliated, sometimes called "nones," are a demographic category including atheists, agnostics, and people who report no religious identity on surveys though they may hold various spiritual, ethical, or cultural beliefs. Estimates from the Pew Research Center place the global unaffiliated population at approximately 1.2 billion. The largest concentrations are in East Asia, particularly in China, where state surveys report that a majority of respondents do not identify with an organized religion, though folk religious practice remains widespread. Western and Northern Europe also have large unaffiliated populations, and the share of unaffiliated respondents has risen among younger generations in the United States, Canada, Australia, and New Zealand.

Scholars emphasize that "unaffiliated" does not correspond neatly to non-belief or to secularism. Many people who mark no religious affiliation on a survey still report belief in God or a higher power, participate in holiday observances, hold spiritual practices such as meditation, or identify culturally with a religious heritage. Others explicitly reject religious belief; atheism as an active identity is more common in some European countries than in most of the world. The growth of the unaffiliated population is a significant feature of twenty-first-century religious demography and is the subject of extensive ongoing research.

Migration, urbanization, and modern communication have made religious diversity a lived reality in most contemporary societies. Cities that were historically dominated by one or two traditions now routinely include adherents of many religions and of none, studying and working alongside one another. The Pluralism Project at Harvard University and the Harvard Divinity School Religious Literacy Project document this changing religious landscape in North America, and similar initiatives exist in Europe, Asia, and beyond. Scholars increasingly study "lived religion," meaning the actual practices and beliefs of ordinary adherents as distinct from official doctrines.

Interfaith dialogue has a long history but accelerated in the modern era. The Parliament of the World's Religions, first convened in Chicago in 1893 and reconvened periodically since 1993, brings together representatives of many traditions to discuss shared ethical commitments and differences. The World Council of Churches coordinates ecumenical dialogue among Christian bodies, and numerous national and local interfaith councils work on community cohesion and shared advocacy. Religious freedom and religious persecution remain global concerns. The United States Commission on International Religious Freedom publishes annual reports documenting conditions for religious minorities worldwide, and the United Nations Special Rapporteur on Freedom of Religion or Belief investigates and reports on violations of the rights protected under Article 18 of the Universal Declaration of Human Rights.

Detailed citations, data references, and institutional sources for all CountryReports content are listed on the Sources page. The following government agencies, academic institutions, and research organizations are the primary authorities we rely on for content about the world's religions. Each link points to the institution's homepage. Demographic figures cited above are drawn from the research organizations listed and change from year to year; readers are encouraged to consult the primary sources for current data.

Research Organizations and Data Archives

• Pew Research Center — Religion and Public Life — Global religious demography, survey data, and topical reports on religion in public life.
• Gordon-Conwell Theological Seminary — Center for the Study of Global Christianity — World Christian Database and global demographic estimates for Christianity and other traditions.
• The Pluralism Project at Harvard University — Research on religious diversity and interfaith engagement in the United States.
• Parliament of the World's Religions — Global interfaith gatherings and published ethical declarations.

Academic Research Centers

• Harvard Divinity School — Religious Literacy Project — Case studies, country profiles, and educational resources supporting the responsible study of religion.
• University of Oxford — Centre for the Study of Religion in the Contemporary World — Research on contemporary religious thought and practice.
• Yale Divinity School — Research and publications across biblical studies, world Christianity, and comparative religion.
• University of Chicago Divinity School — Scholarship across the history, philosophy, and comparative study of religions.

Government and International Bodies

• United States Commission on International Religious Freedom (USCIRF) — Annual reports documenting global conditions for religious minorities.
• United Nations Special Rapporteur on Freedom of Religion or Belief — Reports to the Human Rights Council under the mandate for freedom of religion or belief.
• Library of Congress — Religion Collections — Manuscripts, rare books, and digital collections relating to religious history and practice.
• British Library — Religious and Philosophical Heritage — Collections of sacred texts, religious manuscripts, and related scholarship.

If you notice an error or would like to suggest a correction, please use our contact page to get in touch.