30 – 99

Apostolic Age

From a Galilean movement to churches across the Roman world.

From the ministry and crucifixion of Jesus to the death of the last apostles, the first Christians spread from Jerusalem across the Roman world and wrote the texts of the New Testament.

Cross and Resurrection

The crucifixion of Jesus and the proclamation that he had risen became the foundation of the new faith.

Mission to the Gentiles

Paul's journeys carried the message from Antioch to Greece and Rome, opening it to non-Jews.

First Persecutions

Stephen, James, Peter and Paul died as martyrs under Jewish and Roman authorities.

The New Testament

Letters and Gospels written within two generations became Christianity's founding scriptures.

Population estimate: Johnson & Chung, 'Tracking Global Christianity's Statistical Centre of Gravity, AD 33–AD 2100', International Review of Mission 93 (2004)

100 – 311

Early Church

A persecuted minority that built bishops, creeds and a canon.

In the age of the Apostolic Fathers and apologists, the church developed bishops, creeds and a canon of scripture while facing intermittent and sometimes severe persecution.

Bishops and Apologists

Ignatius, Justin and Irenaeus defended the faith and shaped church order around the bishop.

Age of Martyrs

Local and empire-wide persecutions, from Polycarp to Perpetua, made martyrdom central to Christian identity.

Defining the Faith

Marcion, Montanism and Gnosticism pushed the church toward a canon and a shared rule of faith.

Beyond the Empire

Christianity reached Edessa, Armenia and the Egyptian desert, where Anthony began the monastic life.

Population estimate: Johnson & Chung, 'Tracking Global Christianity's Statistical Centre of Gravity, AD 33–AD 2100', International Review of Mission 93 (2004)

312 – 787

Age of Councils

From imperial recognition to defining Christian doctrine.

From Constantine to the Second Council of Nicaea, Christianity became the religion of the empire, defined its doctrine in seven ecumenical councils, built monasticism and faced the rise of Islam.

Imperial Support

Constantine's conversion and the Edict of Milan (313) opened a new chapter for Christianity.

Ecumenical Councils

Councils at Nicaea, Constantinople and beyond defined key doctrines and confronted heresies.

Expansion and Challenges

Christianity spread across the empire while facing the rise of Islam and new geopolitical realities.

Lasting Legacy

Doctrinal definitions, creeds and church structures established in this era shaped Christianity for centuries.

Population estimate: Johnson & Chung, 'Tracking Global Christianity's Statistical Centre of Gravity, AD 33–AD 2100', International Review of Mission 93 (2004)

788 – 1516

Medieval Church

Christendom at its height: popes, monks, crusaders and schism.

The medieval centuries saw the conversion of northern and eastern Europe, the split between East and West, papal reform, crusades, cathedrals, universities and the crises of Avignon and the Great Schism.

Conversion of Europe

Missions to Slavs, Scandinavians and the Rus' brought nearly all of Europe into the Christian fold.

East and West Divided

Disputes over authority and the creed culminated in the mutual excommunications of 1054.

Papal Monarchy

The Gregorian reform raised papal power over kings, and popes summoned the crusades to the East.

Cathedrals and Schools

Gothic cathedrals, the new friars and scholastics like Aquinas shaped medieval faith and learning.

Population estimate: Johnson & Chung, 'Tracking Global Christianity's Statistical Centre of Gravity, AD 33–AD 2100', International Review of Mission 93 (2004)

1517 – 1647

Reformation

Western Christendom divided, and the church carried worldwide.

Luther, Zwingli, Calvin and the radical reformers divided Western Christianity, while the Catholic Reformation, the Council of Trent and global missions renewed the Roman church amid wars of religion.

Protestant Reformers

Luther, Zwingli, Calvin and the Anabaptists challenged Rome over grace, scripture and authority.

Catholic Renewal

The Council of Trent and new orders like the Jesuits reformed Catholicism and answered Protestantism.

Global Missions

Missionaries followed Spanish and Portuguese empires to the Americas, India, China and Japan.

Wars of Religion

Confessional conflict tore through France, the Low Countries and Germany until the Thirty Years' War.

Population estimate: Johnson & Chung, 'Tracking Global Christianity's Statistical Centre of Gravity, AD 33–AD 2100', International Review of Mission 93 (2004)

1648 – 1869

Enlightenment & Revival

Reason and revolution tested the churches as revival swept the Protestant world.

Between Westphalia and Vatican I, Pietism, Methodism and the Great Awakenings revived Protestantism, revolutions challenged the churches, and a great missionary movement carried Christianity worldwide.

Pietism and Awakening

Pietists, Moravians, Wesley and the Great Awakenings stressed personal conversion and holy living.

Revolution and Secularism

The Enlightenment and the French Revolution weakened established churches and separated church from state.

The Missionary Century

Carey, Morrison, Livingstone and new societies carried Protestant missions to Asia and Africa.

Reform and Abolition

Christian campaigners led the fight against slavery, while Rome answered modernity with the Syllabus of Errors.

Population estimate: Johnson & Chung, 'Tracking Global Christianity's Statistical Centre of Gravity, AD 33–AD 2100', International Review of Mission 93 (2004)

1870 – present

Modern Era

World wars, ecumenism and the southward shift of global Christianity.

From Vatican I to the present, Christianity faced world wars, totalitarian persecution and secularization, while ecumenism, Vatican II, Pentecostalism and growth in the Global South reshaped the faith.

Church Under Pressure

World wars, genocides and communist regimes produced more martyrs than any earlier century.

Ecumenism and Dialogue

The World Council of Churches and Vatican II opened dialogue between long-divided churches.

Pentecostal Growth

From Azusa Street, Pentecostal and charismatic movements grew into a major strand of world Christianity.

The Global South

By the 21st century most Christians lived in Africa, Latin America and Asia.

Population estimate: Center for the Study of Global Christianity, Status of Global Christianity 2026 (World Christian Database)