Christianity is a mixture of ancient Greek philosophy and Hebrew religion, and has had extensive and profound influence on Western culture in history.From the perspective of religious history, Christianity originated from a small sect of Judaism, which was born in Palestine in the first century AD; from the perspective of social consciousness, it should be said that it was formed in the Greco-Roman world in the Mediterranean region. Around the 1st century AD, the Jews in Palestine repeatedly launched uprisings, which were brutally suppressed by the Roman Empire.The Jews in a miserable situation adhere to the Jewish tradition and look forward to the coming of the prophesied Messiah, the Restoration Savior, to save people from suffering.At this time, primitive Christianity appeared in the form of a new sect of Judaism, advocating that "the kingdom of heaven is coming" and calling for "sinners to repent." In the second half of the 1st century, Christianity spread to Syria, Asia Minor, Macedonia, Greece, Rome, and Egypt, and won believers among various ethnic groups. In terms of doctrine, it combined with popular Hellenistic philosophy, ethics, and mysticism, and broke through Judaism. Narrowly restricted, it evolved into a world religion adapted to the Roman Empire.Most of the early Christians were poor people and slaves. They had a strong sense of resistance to Roman rule and social oppression, so they were persecuted by the rulers of the Roman Empire on a large scale.But instead of dying out, Christianity has grown in number and social influence.By the end of the third century, Christianity had spread throughout the Roman Empire and became a social force that could not be ignored.The social composition of the church leadership also changed accordingly. The rich and intellectuals who joined the church changed their attitudes towards the rulers and tried their best to win their tolerance and sympathy; The illegal status of Christianity. At the beginning of the 4th century, under internal and external pressure, the Roman rulers began to change their policy towards Christianity. By the end of the 4th century, it was made the state religion. Christianity finally became the dominant ideology of the Roman Empire.

Due to differences in administrative divisions, languages, and cultural traditions, Christianity evolved into two factions, Eastern and Western.The Eastern School, headed by the Church of Constantinople (now Istanbul), calls itself the "Orthodox Church" (that is, the Orthodox Church, also known as the Orthodox Church). It spread from Macedonia, Greece to Egypt and its east, and the Greek language is common, so it is also called Greek. church.The Western faction, headed by the Church of Rome, calls itself the "Catholic Church" (that is, the Universal Church, or Catholicism in China). It occupies areas from France, Italy to Carthage in North Africa and the areas west of it. Latin is commonly used, so it is also called the Latin Church.The Eastern faction is largely attached to the state power, and the imperial power directly intervenes in religious affairs and determines the doctrine, which is related to the long-term unification and autocratic centralization of the Byzantine Empire.The Western faction was independent of the state power and even intervened in secular affairs. This was related to the demise of the Western Roman Empire under the barbarian invasion and the long-term political fragmentation. At the end of the 6th century, the Bishop of Rome (also known as the Pope) became the leader of the western church and gained political power.The bishop of Constantinople, with the support of the Byzantine emperor, claimed to be the universal patriarch, and the confrontation with Rome was becoming a foregone conclusion.

During the process of European feudalization in the Middle Ages, Christianity spread to most European countries mainly by the decrees of various feudal dynasties.The abbots of churches and monasteries became feudal lords everywhere and were the main pillars of European feudal society; the church monopolized culture and education, and in the ideological field, put politics, law, philosophy, and ethics under the control of theology.Since the late 9th century, the struggle for the supreme power of the church has become more acute. In 1054, the Patriarch of Constantinople and the Pope issued excommunication orders, resulting in the official division of the Eastern and Western Churches. From the 11th century to the 13th century, the Pope of Rome launched seven Crusades, making the Pope's power reach its peak in the 13th century.Since then, due to the internal corruption of the church, the struggle between the teaching power and the royal power has failed, and the pope's prestige and power have declined sharply.Among the poor peasants, urban commoners and emerging citizens, various heretical factions continued to appear.In addition to cooperating with secular governments and organizing crusades to suppress them, the Holy See also used religious orders to organize heresy inquisitions, hunted down, suppressed, and strangled progressive ideas.

In the first half of the 16th century, religious reform movements broke out in Germany, Switzerland, the United Kingdom, the Netherlands, and Scandinavia, denying the authority of the Pope, emphasizing different aspects of traditional teachings, and reforming the church liturgy system. In 1517, Martin Luther strongly advocated the religious reform, emphasizing "justification by faith", which means that believers can be called "righteous" before God, all by trusting in Jesus, not by fulfilling church rules.He founded the Lutheran Church with the support of the princes.In Switzerland and France, Zwingli and Calvin successively initiated reforms, forming the Calvinist church with the support of the citizens, emphasizing that the destiny of the world, good and evil, is predetermined by God.The Reformation in Scotland and Holland promoted national independence.In England, the Church of England headed by the king was finally established.Scandinavian countries successively carried out top-down reforms and established Lutheran churches.These denominations that broke away from the Roman Catholic Church were later collectively referred to as "Protestantism" or "Protestantism".

Facing the powerful impact of the Reformation Movement, the Catholic Church took a series of measures to reform internally, correct its shortcomings, and formulate unified countermeasures.At the same time, in order to fight against Protestantism, the Holy See reformed the religious order system and established new types of religious orders and missionary orders (Foreign Missionary Society). Among them, the Jesuit Society established in 1534 had the greatest influence.The Holy See used the support of conservative forces in various countries to resist the development of Protestantism with religious orders, stabilized Catholicism in some parts of Europe, and spread Catholicism to vast areas in America, Africa and Asia.

In the middle of the 16th century, the Puritan movement rose in England.Its Calvinism in doctrine and republican principles in organization fit the needs of the bourgeoisie and the new aristocracy, so it became the ideological cloak of the British bourgeois revolution. In 1620, many Puritans moved to North America, and Protestantism was widely spread in North America, and new sects such as Congregationalism, Baptistism, and Quakerism were formed. From the 17th to the 18th centuries, the German Pietist Movement, the British Evangelical Revival Movement, and the Great Awakening Movement in the United States formed a Christian revival that focused on personal beliefs. In the 19th century, Protestantism emerged with liberal theology.Conservative forces who adhere to traditional teachings launched the Oxford Movement in England.In the United States, fundamentalist theology emerged in the early 20th century.Protestant missionary activity started a little later.After European immigrants spread Protestantism to North America and Australia, Western European countries successively established missionary associations and competed to preach to various places.The spread of Christianity in modern times is inseparable from the invasion and expansion of colonialism.

After the 20th century, in order to adapt to the diversification and non-religion of modern society, Christianity absorbed modern philosophy, social science and natural science in theology. Thomism, existential theology, secular theology, hope theology, liberation theology, and process theology.Fundamentalists hold a critical attitude towards these theologies, but while emphasizing spreading the gospel and pursuing personal salvation, they also pay attention to various social and moral issues, called New Evangelicals.At the same time, in terms of factions and organizations, the universal church movement initiated by some missionary organizations has gradually developed into a worldwide movement for the reunification of various denominations of modern Christianity. In 1948, the World Federation of Christian Churches was formally established in Amsterdam, the Netherlands.The association includes most Protestant and Orthodox churches, with the purpose of "unity of the church, unity of the world, and unity of mankind" and serves as a consultative function for members.

At the first Vatican Council in 1869-1870, the Holy See emphasized the supreme authority of the Pope and reiterated that the Pope's words on faith and ethics are "never wrong." At the beginning of the 20th century, a trend of modernism emerged within the Catholic Church, advocating the reconciliation of the contradictions between philosophy, science and traditional teachings, but it was brutally suppressed by the Holy See.It was not until the Second Vatican Council from 1962 to 1965 that the Holy See began to change its rigid position, put forward innovation and dialogue guidelines, and adopted new measures to "keep up with the times."After the meeting, the Holy See held dialogues with other denominations and religions, and contacted and cooperated with the federation.

Today, there are more than 1.6 billion Christians in the world, accounting for about 1/3 of the world's population.Among them, there are more than 900 million Catholics, about 500 million Protestants, and about 200 million Orthodox Christians.Christianity is still the world religion with the largest number of believers and wide influence.