History of Christianity

The history of Christianity begins with Jesus, a Jewish teacher. He was crucified in Jerusalem around AD 30–33. His followers believed he was the incarnation of God and had risen from the dead. Over many years, Christianity spread around the world and became the world's largest religion with over two billion adherents worldwide.

At first, Christianity was a small movement of people in cities. Its religious text was written in the first century. A church government formed, and by the third century, over a million people followed it. Constantine the Great made Christianity legal in 313 with the Edict of Milan. Christian art, architecture, and literature grew, but different beliefs caused divisions.

After Rome fell in 476, monks helped keep culture alive and supported their communities. Early Muslim conquests affected many Christian groups in the Middle East and North Africa, but Christianization continued in Europe and Asia, helping shape Eastern Europe. In the 14th century, problems in the church and other troubles in Europe led to the Reformation in the 16th century, when Protestantism began.

In the twentieth century, Christianity grew less common in much of the Western world but increased in the Global South, especially in Southeast Asia and Sub-Saharan Africa. Today, Christianity is practiced in many different languages and ways.

Early Christianity (c. 27 – fourth century)

Main article: Early Christianity

First century

Main article: Christianity in the 1st century

Further information: Chronology of Jesus and Historical Jesus

Christianity started with Jesus of Nazareth, a Jewish teacher in Galilee and the Roman province of Judea. Jesus was crucified around the year 30. His followers believed he was the Messiah and had come back to life. They met in small groups in homes, led by elders or bishops. Women were important in these groups.

The first Christians were mostly Jewish and met in private homes. They believed Jesus was the Messiah. They practiced baptism and the Eucharist. The twelve followers of Jesus, called the Apostles, and later Paul the Apostle, traveled to share their message. Christianity spread through cities along trade routes to places like Rome, Alexandria, Antioch, Ephesus, and Carthage.

Ante-Nicene period (100–312)

Main article: Christianity in the ante-Nicene period

Further information: Great Church and Gnosticism

Christianity spread to Syria, Mesopotamia, North Africa, and across the Mediterranean. By the third century, it reached Roman Britain. The belief in Jesus brought new ideas and a strong sense of community. Christians were sometimes treated badly by the Roman empire for not following Roman traditions, but the faith kept growing.

By the year 200, there were over 200,000 Christians, and by 250, over a million. Early Christian art, found in the catacombs of Rome, often showed Jesus as the good shepherd.

Late antiquity (313 – c. 600)

Main article: Christianity in late antiquity

See also: Late Antiquity § Sculpture and art, and Church Fathers

Late Antiquity was an important time for Christianity. In 313, Emperor Constantine said people could follow any religion they wanted. He helped Christianity grow by supporting church leaders and building churches. By the end of the fourth century, most cities in the Roman Empire had churches.

Artists and writers made beautiful works that mixed old Roman styles with new Christian ideas. Important church leaders wrote many books that shaped Christian beliefs. Monks began to live together in groups, helping others and keeping traditions alive.

Christianity spread to many places, even during difficult times. It became the official religion in the Kingdom of Armenia in 301 and later in other areas too.

During this time, church leaders met to talk about important beliefs and how to stay united. These meetings helped Christians agree on who Jesus was and what the church should teach. Even with differences, many worked to keep the faith strong and growing.

Early Middle Ages (c. 600–1000)

Further information: Early Middle Ages

See also: Christian monasticism, Byzantine Iconoclasm, Illuminated manuscript, and Insular art

By the early 600s, Christianity had spread around the Mediterranean. Between 632 and 750, new rulers took over places like the Middle East, North Africa, and the Iberian Peninsula. Many churches disappeared, but some Christian groups in faraway places stayed safe. During this time, wars helped the Eastern Roman Empire become the Byzantine Empire. Western Europe stayed poor, divided, and relied on the church.

During this time, attacks and problems left some places without churches, so Christianity mixed with local customs. But by the end of this time, the idea that all Christians were one group began.

Monasticism and art

Until the end of the Early Middle Ages, monks helped keep Western culture alive. Monasteries took care of orphans and travelers, and gave food to people in need. They helped people learn to read, made art and crafts, and copied old books. Monks made special books called illuminated manuscripts. Most schools during this time were linked to monasteries.

This was a time of change, and holy men became very important. Monasteries became more organized and gained their own power. They were also important for medicine, with many monasteries having hospitals and helping improve medical knowledge.

In the East, people created sacred art, using old styles to make icons that connected people to God. In the 720s, a ruler named Leo banned these pictures of Christ, saints, and Bible stories, and destroyed many early artworks. The West did not agree with this. By the 1000s, Byzantine culture began to bring back its art.

Regional differences

Eastern Europe met Christianity when Rome ruled there, but it was Byzantine Christianity, brought by the saints Cyril and Methodius in the 800s, that helped shape its countries. Leaders used this new faith to strengthen their rule and bring people together. These brothers made the Glagolitic alphabet to translate the Bible into the local language. Their students then made the Cyrillic script, which helped people learn to read and became important for all Slavic nations.

In Western Europe, canon law helped create important rules about promises of loyalty. These rules became part of regular laws. Inside the system of feudalism, the church helped create a new way for kings to be holy leaders, and in 800, Charlemagne became one when Pope Leo III crowned him emperor. Charlemagne started many changes that began the Carolingian Renaissance, a time when learning and culture grew again.

In Russia, Vladimir of Kiev was baptized in 989, and this event is linked to the Kievan Rus people turning to Christianity. Their new religious setup included leaders who controlled a church that depended on them for money.

Viking attacks in the 800s and 900s destroyed many churches and monasteries, but this also led to changes. People who had money tried to rebuild, and by the middle of the 1000s, the Latin Church became richer, more organized, better educated, and more thoughtful about spiritua matters. Papal power grew in the 900s when William IX, Duke of Aquitaine and other important people put their monasteries under the protection of the pope.

High Middle Ages (c. 1000–1300)

Further information: High Middle Ages

In this time, joining the Christian community usually started with being baptized as a baby. People were expected to know basic prayers and beliefs, rest and celebrate on special days, attend church services, fast at certain times, take part in a special meal called communion each year, help others, and receive special blessings before death. From about 1198 to 1216, a leader named Pope Innocent III made the office of the pope very powerful.

During this period, important ideas about Christian practices were formed, like the seven important religious actions and rules about marriage. The idea of a place called Purgatory where people prepare for heaven became official. In 1215, it became a rule that everyone must go to confession. Special prayers called the rosary were also created because many people loved and respected Mary, the mother of Jesus.

Monasteries, which were like religious communities, became important at first but later lost some of their influence. Schools connected to cathedrals grew, and new universities were formed. Laws and writing became more organized, and more people learned to read and write.

The effort to make the church independent from kings and emperors began with reforms led by Pope Gregory VII from 1073 to 1085. This meant the church wanted to be in charge of its own matters without kings interfering. There was a big disagreement called the Investiture Controversy about who could choose church leaders.

There were also separations within Christianity. One group, the Church of the East, remained separate and spread far across many lands. Another separation happened in 1054 when the church in the Byzantine Empire became known as Eastern Orthodoxy.

Christians in some areas faced difficult times under new rulers. Some Christians chose to leave, others changed their religion, and some asked for help from faraway leaders. This led to journeys known as the Crusades.

The idea of knights as brave and honorable Christian warriors became popular. Also, new ways of thinking about learning and science began to grow.

New groups formed to help spread and protect Christian teachings. Some people were accused of having different beliefs, and special church courts were set up to talk about these matters.

During this time, there were also changes in how Jewish people were treated. Some faced unfair treatment or were forced to leave their homes.

In parts of Europe, efforts continued to bring all people to follow Christianity. Leaders taught that people should choose to follow their beliefs.

Renaissance and Reformation (c. 1300–1650)

Further information: Renaissance

Division in the West

Many challenges faced people in Europe during the 1300s and 1400s, such as disease, hunger, wars, and unrest. This made some people feel worried. Some people criticized the church.

During this time, the leader of the church, called the Pope, moved away from Rome to a place called Avignon in France. This made the Pope seem weaker. Later, more than one person claimed to be the Pope, causing confusion.

Some people, like John Wycliffe and Jan Hus, spoke out against problems in the church. Sadly, Jan Hus was treated unfairly.

East and Renaissance

In the Eastern part of the Christian world, there were also changes. After the city of Constantinople fell, the Orthodox church faced new challenges but continued its work.

The church in Western Europe supported art and building projects, helping to create beautiful structures and support artists.

Colonialism and missions

Main article: Christianity and colonialism

As European countries explored and settled in new lands, Christian missionaries traveled with them. These missionaries brought their faith to new places, sometimes working with local people to build schools and hospitals. However, their work did not always match the goals of the governments taking control of these lands.

Women, witch frenzy, and Modern Inquisition

See also: Witch trials in the early modern period

During this time, many people, especially women, were unfairly accused of being witches. These accusations came from neighbors and were based on fear and misunderstanding. Many trials happened, but most people accused were found not guilty. The church tried to make sure evidence was needed before making accusations.

Reformation

In 1517, a man named Martin Luther started what is called the Reformation by sharing his ideas about how the church could change. He believed that people could find their own way to understand their faith without always needing the Pope or church leaders. His ideas led to the creation of new church groups, including Lutheran, Reformed, and Anglican traditions.

The Roman Catholic Church responded with its own set of changes, known as the Counter-Reformation, to address the concerns raised by Luther and others. This included forming new groups within the church and making changes to how the church operated.

Modern period (1650–1945)

Ideological movements

After Christian ideas were no longer shared across Europe, some kings were very strict. This made people question Christianity, especially during a time called the Age of Enlightenment. For many years, people asked for the right to practice their own religion. By the late 1600s, even thinkers who did not believe in religion said people should be allowed to choose their own beliefs.

As time went on, many people in Europe began to study the Bible in new ways. Some groups, especially Protestants, started new movements to live more holy lives. These ideas spread to places like the Thirteen Colonies, where they helped start a big religious revival in the 1700s. This revival led to new church groups forming, such as the Methodist church. In Europe and America, both Protestant and Catholic groups helped the poor, supported families, and provided medicine and education.

Nineteenth and twentieth centuries

In the 1800s and early 1800s, there was another big religious revival. This led to the start of new church groups, such as Mormons and Jehovah’s Witnesses. These groups focused on following the practices of early Christians. This revival also helped with important social changes, like supporting women’s rights, stopping drinking and other unwholesome activities on Sunday, teaching people to read, and ending slavery.

Many Christians worked hard to end the slave trade that had gone on for hundreds of years. Their efforts helped change laws and improve lives in many parts of the world.

A later religious revival in the late 1800s inspired Christian missionaries to travel around the world. These missionaries helped teach people to read and write by translating the Bible into local languages. Their work helped many cultures grow and change.

Some Christians began to focus more on ideas from the past, while others reacted against new ways of thinking. These different views led to changes in how churches operated.

Russian Orthodoxy

In the early 1700s, leaders in Russia took control of the Orthodox Church. Later, when communist leaders came to power, they saw the church as an enemy. They tried to stop people from practicing their religion, but the Orthodox Church kept contributing to the culture and teachings of the people.

After World War II

Further information: World Christianity

Before 1945, many people around the world were Christians, and most lived in Europe, Russia, and the Americas. By 2025, about 31% of adults worldwide call themselves Christian, but they are not mostly in the West anymore. Christianity has declined in Europe. From 2019 to 2024, about 60% to 64% of adults in the United States were Christian. Even so, it is expected that fewer than a quarter of the world's Christians will live in western areas by 2060.

After World War II, as countries became independent, Christian groups grew quickly in many of these new nations. In 1900, about 6.5% of Africa's people were Christian; by 1960, this rose to nearly 21%, and by 2005, about half of Africans were Christian. Christianity also grew fast in parts of Asia, especially Korea, and among young people in China.

With the end of rule by other countries, Christianity grew in some Eastern European nations but declined in others. Catholic countries became less religious, while Orthodox countries saw more people returning to the church. Orthodox Christianity became important again in some parts of the former Soviet Union after 1991.

Today, Christianity is found on all seven continents and in many cultures. It includes over three thousand languages. Most Christians now live outside North America and Western Europe, and slightly more than half are women. In 2017, Christianity was the world's largest religion with about 2.4 billion followers, making up about 31.2% of the world's population.

The Second Vatican Council from 1962 to 1965 made many changes in the Catholic Church, bringing reforms and improving relationships with other Christian groups.

In recent years, Christianity has faced challenges from people who do not see religion as important. Some places, like Southeast Asia and sub-Saharan Africa, still see Christianity growing, while in many Western countries, fewer people attend church.

Pentecostalism, a lively branch of Protestantism, has become very popular. By 2025, it is expected to be the largest part of Protestantism and one of the fastest-growing Christian movements.