History of Christianity

The history of Christianity begins with Jesus, an itinerant Jewish preacher and teacher, who was crucified in Jerusalem c. AD 30–33. His followers proclaimed that he was the incarnation of God and had risen from the dead. In the two millennia since, Christianity has spread across the world, becoming the world's largest religion with over two billion adherents worldwide.

Initially, Christianity was a mostly urban grassroots movement. Its religious text was written in the first century. A formal church government developed, and it grew to over a million adherents by the third century. Constantine the Great issued the Edict of Milan legalizing it in 313. Christian art, architecture, and literature blossomed during the fourth century, but competing theological doctrines led to divisions.

After the fall of Rome in 476, western monks preserved culture and provided social services. Early Muslim conquests devastated many Christian communities in the Middle East and North Africa, but Christianization continued in Europe and Asia and helped form the states of Eastern Europe. In the 14th century, the Western Schism and several European crises led to the 16th-century Reformation when Protestantism formed.

In the twentieth century, Christianity declined in most of the Western world but grew in the Global South, particularly Southeast Asia and Sub-Saharan Africa. In the twenty-first century, Christianity has become the most diverse and pluralistic of the world's religions embracing over 3000 of the world's languages.

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 began with Jesus of Nazareth, a Jewish man and teacher in Galilee and the Roman province of Judea during the first century. Jesus was crucified around the year 30, and his followers believed he was the Messiah and had risen from the dead. They gathered in small groups in homes, with leaders called elders or bishops overseeing them. Women were important members of these early groups.

The first Christians were mostly Jewish and met in private homes. They believed Jesus was the Messiah and practiced rituals like baptism and the Eucharist. The twelve followers of Jesus, known as the Apostles, and later Paul the Apostle, traveled to share their message. Christianity spread through cities along trade routes, reaching 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 as far as Roman Britain. The belief in Jesus brought new ideas and a strong sense of community. Christians were sometimes persecuted by the Roman empire for not following Roman traditions, but the faith continued to grow.

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 a time of big changes for Christianity. In 313, Emperor Constantine said that all religions could be practiced freely. He also 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 created beautiful works inspired by both old Roman styles and new Christian ideas. Important church leaders wrote many books that helped shape Christian thinking. Monks began living together in communities, helping others and keeping traditions alive.

Christianity spread to many places, even where there were wars and challenges. 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 discuss important beliefs and how to stay united. These meetings helped create shared understandings among Christians about who Jesus was and what the church should teach. Even with differences, many worked hard 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. However, between 632 and 750, Islamic caliphates conquered the Middle East, North Africa, and the Iberian Peninsula. Most urban Asian churches disappeared, but some Christian communities in remote areas survived. In the same period, war on multiple fronts contributed to the Eastern Roman Empire becoming the independent Byzantine Empire. Until the eighth century, most of Western Europe remained largely impoverished, politically fragmented, and dependent on the church.

During this period, invasion, deportation, and neglect left some communities without a church, allowing Christianity to blend with local traditions. Nevertheless, the idea of all Christians united as one group emerged at the end of this age.

Monasticism and art

Until the end of the Early Middle Ages, Western culture was preserved and passed on primarily by monks. Monasteries served as orphanages and inns for travelers, and many provided food for those in need. They supported literacy, practiced classical arts and crafts, and copied and preserved ancient texts. Dedicated monks created illuminated manuscripts. From the sixth to the eighth centuries, most schools were connected to monasteries.

This was an age of uncertainty, and the role of holy men became increasingly important. Monasteries became increasingly organized, gradually establishing their own authority. Medical practice was highly important, and medieval monasteries were known for their public hospitals and contributions to medicine.

The East developed an approach to sacred art, adapting ancient portraiture in icons as intercessors between God and humankind. In the 720s, the Byzantine Emperor Leo banned the pictorial representation of Christ, saints, and biblical scenes, and destroyed much early representational art. The West condemned this. By the tenth and early eleventh centuries, Byzantine culture began to recover its artistic heritage.

Regional differences

Eastern Europe had been exposed to Christianity during Roman rule, but it was Byzantine Christianity, brought by the ninth-century saints Cyril and Methodius, that was integral to the formation of its modern states. Dukes and kings used the new faith to solidify their position and promote unity. The brothers developed the Glagolitic alphabet to translate the Bible into the local language. Their disciples then developed the Cyrillic script, which spread literacy and became the cultural and religious foundation for all Slavic nations.

In Western Europe, canon law was instrumental in developing key norms concerning oaths of loyalty. These norms were incorporated into civil law. Within the tenets of feudalism, the church created a new model of consecrated kingship, and in 800, Charlemagne became its recipient when Pope Leo III crowned him emperor. Charlemagne engaged in a number of reforms which began the Carolingian Renaissance, a period of intellectual and cultural revival.

In Russia, the baptism of Vladimir of Kiev in 989 is traditionally associated with the conversion of the Kievan Rus. Their new religious structure included dukes maintaining control of a financially-dependent church.

Viking raids in the ninth and tenth centuries destroyed many churches and monasteries, inadvertently leading to reform. Patrons competed in rebuilding so that by the mid-eleventh century, a wealthy, unified, better-organized, better-educated, more spiritually sensitive Latin Church resulted. There was another rise in papal power in the tenth century when William IX, Duke of Aquitaine, and other powerful lay founders of monasteries, placed their institutions under the protection of the papacy.

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 by paying fees, 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, the right reward for work, 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. This conflict showed the growing power of the pope and the church.

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 who followed Islam. Some Christians chose to leave, others changed their religion, and some asked for help from faraway leaders. This led to calls for help that brought many people together for journeys known as the Crusades. These journeys had mixed results and also changed how people in Europe saw themselves and others.

The idea of knights as brave and honorable Christian warriors became popular. Also, new ways of thinking about learning and science began to grow, partly because monks found old writings in libraries left behind by people who had moved away.

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. These courts depended on local leaders for support.

During this time, there were also changes in how Jewish people were treated. Some were blamed for sicknesses or other problems, and sometimes faced unfair treatment or were forced to leave their homes.

In parts of Europe, efforts continued to bring all people to follow Christianity, sometimes by force, even though 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, including diseases, hunger, wars, and unrest. This made some people feel that the end of the world might be coming. These feelings often led to criticism of 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, there was a time when more than one person claimed to be the Pope, causing confusion.

Some people, like John Wycliffe and Jan Hus, spoke out against what they saw as problems in the church. Sadly, Jan Hus was treated unfairly and faced serious consequences for his beliefs.

East and Renaissance

In the Eastern part of the Christian world, there were also changes. After the city of Constantinople fell to a different ruler, the Orthodox church faced new challenges but managed to continue its work.

The church in Western Europe became a big supporter of art and building projects, helping to create beautiful structures and support artists.

Colonialism and missions

Main article: Christianity and colonialism

As European countries started exploring and settling 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 align with the goals of the governments that were 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 often 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 to tell them what to believe. 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

The time after Christian ideas were no longer shared across Europe saw kings who were very strict in their rules. This led some people to question Christianity, especially during a time called the Age of Enlightenment. For many years, people had been asking for the right to practice their own religion. By the late 1600s, even thinkers who did not believe in religion started to say people should be allowed to choose their own beliefs.

As time went on, many people in Europe began to think more about studying the Bible in a new way. 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 very hard 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, about a third of the world's people were Christians, and most of them lived in Europe, Russia, and the Americas. By 2025, about 31% of adults worldwide identify as Christian, but they are no longer mainly in the West. 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 gained independence, 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.