What Is Christendom? When and Where was It?

Learn the origins and timeline of the historical "Christendom" that included most of Europe and beyond!

Updated Aug 04, 2021
What Is Christendom? When and Where was It?

The word "Christendom" first appeared in the 12th century, arising from the Middle English term cristendom, and the Old English cristendōm. Before the schism of Orthodoxy and Catholicism in the 11th century, there was one church of Christianity, which was all of Christendom. Now that there are thousands of distinctly identifying Christian churches, the affiliation of Christendom is more complex.

"Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit" ~ Matthew 28:19

Definition of Christendom

According to Wikipedia, "Christendom historically refers to the "Christian world": Christian states, Christian-majority countries and the countries in which Christianity reigns or prevails."

Christendom is plainly defined as "the part of the world in which Christianity prevails" by Merriam-Webster.

What Does Christendom Refer To?

The term "Christendom" largely refers to the worldwide adherents of the Christian faith, with religious practices and beliefs drawn from the teachings of the Bible, primarily the New Testament. Found throughout the world, Christendom includes literally billions of people among many countries and peoples of different ethnicities. Furthermore, Christendom also refers to those countries where Christianity is the national or territorial religion.

Not all those who reside within the historical “Christendom” are followers of the Christian faith. The once-Christian European nations are still nominally what is known as “Christendom,” but in large part, biblical Christianity has been forgone in favor of secular humanism, with the rise of theories such as Darwinism and the Big Bang.

Christianity Vs. Christendom

The distinction between Christianity and Christendom is found at the theological and societal levels. We found a good explanation in an article from The Dispatch, saying, 

"Think of the distinctions roughly like this—Christianity is the faith, Christians are believers in the faith, and Christendom is the collective culture and institutions (universities, ministries) of the faith."

According to Brittanica, "After the dissolution of the Roman Empire, the idea arose of Europe as one large church-state, called Christendom. Christendom was thought to consist of two distinct groups of functionaries: the ecclesiastical hierarchy, and the secular leaders. In theory, these two groups complemented each other, attending to people’s spiritual and temporal needs, respectively."

The Timeline of Christendom

Constantine and the Dawn of Christendom

The post-apostolic period concerns the time roughly after the death of the apostles when bishops emerged as overseers of urban Christian populations. The earliest recorded use of the terms Christianity and Catholic, dates to this period, the 2nd century, attributed to Ignatius of Antioch circa 107. Early Christendom would close at the end of imperial persecution of Christians after the ascension of Constantine the Great and the Edict of Milan in AD 313 and the First Council of Nicaea in 325.

According to Malcolm Muggeridge (1980), Christ founded Christianity, but Constantine founded Christendom. Constantine was the first Roman emperor to convert to Christianity. Although he lived much of his life as a pagan, and later as a catechumen, he began to favor Christianity beginning in 312, finally becoming a Christian and being baptized.

The age of Constantine marked a distinct era in the history of the Roman Empire. He built a new imperial residence at Byzantium and renamed the city Constantinople (now Istanbul) after himself. It subsequently became the capital of the Empire for more than a thousand years, the later Eastern Roman Empire is referred to as the Byzantine Empire by modern historians.

The Middle Ages

"Christendom" has referred to the medieval and renaissance idea of the Christian world as a political entity. In essence, the earliest vision of Christendom was a vision of a Christian theocracy, a government founded upon and upholding Christian values, whose institutions incorporate Christian doctrine. During this time, members of the Christian clergy wield political authority.

The Church gradually became a defining institution of the Roman Empire. Emperor Constantine issued the Edict of Milan in 313 proclaiming toleration for the Christian religion, and convoked the First Council of Nicaea in 325 whose Nicene Creed included belief in "one holy catholic and apostolic Church". Emperor Theodosius, I made Nicene Christianity the state church of the Roman Empire with the Edict of Thessalonica of 380.

By the 10th century, the religious and cultural community known as Christendom had come into being and was poised to enter a prolonged period of growth and expansion. Important progress had taken place well before this period, however. Beginning in the last years of the Roman Empire, the central institutions of medieval Catholic Christianity had gradually evolved, laying the foundation for the great advances of the later Middle Ages and beyond.

The Reformation

Developments in western philosophy and European events brought change to the notion of the Corpus Christianum. The Hundred Years' War accelerated the process of transforming France from a feudal monarchy to a centralized state. The rise of strong, centralized monarchies denoted the European transition from feudalism to capitalism.

In the Holy Roman Empire, the Peace of Augsburg of 1555 officially ended the idea among secular leaders that all Christians must be united under one church. The principle of cuius regio, eius religio ("whose the region is, his religion") established the religious, political, and geographic divisions of Christianity, and this was established with the Treaty of Westphalia in 1648, which legally ended the concept of a single Christian hegemony in the territories of the Holy Roman Empire, despite the Catholic Church's doctrine that it alone is the one true Church founded by Christ.

Subsequently, each government determined the religion of its own state. Christians living in states where their denomination was not the established one were guaranteed the right to practice their faith in public during allotted hours and in private at their will.

Age of Enlightenment: End of Christendom

The Age of Enlightenment and the formation of the great colonial empires together with the decline of the Ottoman Empire marked the end of the geopolitical "history of Christendom". Instead, the focus of Western history shifts to the development of the nation-state, accompanied by increasing atheism and secularism, culminating with the French Revolution and the Napoleonic Wars at the turn of the 19th century.

American Catholic bishop Thomas John Curry stated in 2001 that the end of Christendom came about because modern governments refused to "uphold the teachings, customs, ethos, and practice of Christianity." He asserted that the First Amendment to the United States Constitution established in 1791 and the Second Vatican Council's Declaration on Religious Freedom in 1965 are two of the most significant documents causing the end of Christendom.

Navigating the modern world as Christians can be confusing and difficult, find topical answers about the Christian faith in our Wiki section!


Christendom - Wikipedia

Christendom | European History - Britannica

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