Religion in Europe

History of Christianity in Europe

The religion of the Greeks and the Roman Empire was labeled "paganism" by the later predominant Christian faith. The dominance of Christianity meant all other religions were considered heretic–even unofficial forms of Christianity.

Fig. 2: The Baptism of Constantine, imagined by Raphael's students, 1517.

The Edict of Milan in 313 ended the persecution of Christians. By this decree, Emperor Constantine declared that the Christian religion should be protected and tolerated within the Empire. While he likely did not convert to Christianity, he appreciated the faith. His actions paved the way for Emperor Theodosius to declare Christianity the Roman Empire's official religion in 391.

Religion in Medieval Europe: Christianity Hegemony

By the tenth century, the Pope in Rome was the central figure of all Christians–which is to say all of Europe. He wielded considerable political and ecclesiastical power over the Christian kings and feudal lords.

Gregorian reform in the eleventh century solidified the Church's administration and hierarchy and sought to weed out corruption within the clergy.

The Medieval Church

The Medieval Church was very concerned about rival religions, which they considered heretical. Historian R.I. Moore argues that as the Church gained power, it focused on rooting out those who did not conform to their version of Christianity.¹ This need to drive out other faiths led to the Crusades and the Inquisition.

The Crusades

The Crusades began as a plea for military aid from the Byzantine Emperor to Pope Urban II in 1095. The Pope saw an opportunity to rally against a common enemy: Muslims. Thus, a series of holy wars began.

Fig. 3: The Council of Clermont, where Pope Urban II first preached the Crusades, illustrated by Jean Colombe in the manuscript Passages d'outremer, c.1474.

The fervor generated by the Crusades had disastrous consequences for non-Christians in Europe.

The Inquisition

By the thirteenth century, the Church was obsessed with imposing control over what Europeans believed. In the early thirteenth century, Pope Innocent III created a mechanism for rooting out heresy: the Inquisition, a court of inquiry designed to identify and exterminate heretics. Inquisitors would rely on accusation and questioning to identify potential heretics and torture to extract confessions from the accused.

Fig. 4: Galileo before the Inquisition by Joseph-Nicolas Robert-Fleury, 1847.

The most infamous Inquisition was the Spanish Inquisition of the late fifteenth century. The monarchs, Isabella of Castile and Ferdinand of Aragon, established the Spanish Inquisition to root out hidden non-Christians.

Religion in Europe in the 1500s

The sixteenth century fundamentally altered the face of religion in Europe. The Protestant Reformation, the Catholic Counter-Reformation, and the Wars of Religion bifurcated Christianity.

• The Catholic Church, despite its reforms, lost the hegemony of Europe it enjoyed during the Middle Ages.
• Protestantism firmly entrenched itself in many regions in the northern region.

The Protestant Reformation

The Catholic Church, in the eyes of many Europeans of the late Middle Ages, was a corrupt institution.

The Protestant Reformation began in Wittenberg, in 1517. Martin Luther, a German priest who protested against the Church many times before, proposed reforms in a text comprised of ninety-five theses. His bite-size theses, no more than a sentence long each, rapidly spread in the region and soon beyond.

Fig. 5: Martin Luther refusing to recant his theological ideas at the Diet of Worms by Anton von Werner, 1877.

Luther opted for a personal relationship between a person and God and the importance of reading the Bible for oneself. These two revolutionary ideas weakened the central place of Catholic clergy in the practice of faith and, by extension, daily life. As a result, the Church denounced Luther and named him a heretic, but his ideas had given him powerful friends. Frederick III, Elector of Saxony, protected Luther and sheltered him not only because he agreed with him theologically but also because helping him was a way to protest against the political regime of the Catholic Holy Roman Emperor Charles V.

The Counter-Reformation

The Catholic Church was faced with the destruction of its carefully cultivated religious monopoly. In 1545, Pope Paul III called the Council of Trent to reform the Catholic Church and find a way to heal the divide between the Catholics and Protestants brought on by the Protestant Reformation. The Council initiated reforms in Catholic Church practices known as the Counter-Reformation. However, reconciling with the Protestants proved an impossible task for the Church. By the time the Council issued significant reforms such as establishing an educational system for clerics, it was 1562, and the Protestant Reformation had been gaining ground in Europe for decades.

The Wars of Religion

The Protestant Reformation caused a series of European wars of religion to break out, particularly in areas with Catholic kings, such as the Holy Roman Empire and France. The Wars of Religion were caused by a breakdown of understanding of whether the state, the people, or the papacy had religious authority. Catholic kings fought for the power to enforce their religion universally in their territories. Protestants fought for the freedom to choose their faith for themselves and not be persecuted for it. These Wars raged in the Holy Roman Empire from 1519 to the Peace of Augsburg in 1555. Additionally, the French Wars of Religion lasted from 1534 to 1598.

Religion in Modern Europe

Religion continued to change during the Modern Era with the rise of the Enlightenment. Furthermore, this era saw degrees of separation between church and state in Europe, weakening the centuries-long connection between religion and politics.

The Enlightenment

The Enlightenment that emerged in the late seventeenth and eighteenth centuries brought new techniques to explain the seemingly unexplainable. Enlightenment thinkers began using rationalism and critical thinking to explain the natural world. This new practice caused some to question their faith and religion's place at the center of politics, again changing the European religious climate. One cornerstone of Enlightenment thought was religious tolerance.

Major Religions in Europe Today

Today, the dominant religion in Europe is still Christianity. According to a survey conducted in 2019, more than 70% of the European Union's population considered themselves Christians. Included in the seventy percent are 41% who selected Roman Catholic as their religion, followed by Eastern Orthodox at 10%, Protestant at 9%, and other Christians at 4%. Islam made up 2 percent of religious Europeans. Interestingly, 17% considered themselves non-believers or Agnostics, and 10% labeled themselves Atheists. Judaism, it seems, was lumped into the 4% "other religions" category.

Most prominent religion by country, based on a 2019 Eurobarometer survey. Dark blue: More than 75% Catholic. Medium Blue: 50-75% Catholic. Light Blue: Catholic Majority. Purple: 50-75% Protestant. Red: More than 75% Orthodox. Orange: 50-75% non-religious. Yellow: Non-religious majority. Brown: 30% Catholic, 30% non-religious.

Because of secularization during the Modern era, many Europeans do not believe religion holds that much importance in their daily lives. A Gallup poll in 2008 asked Europeans this question and grouped the data by home country. It showed that, at the lowest, only 16 percent of Estonians found religion important, contrasted with 90 percent of Georgians and residents of Kosovo.

While religion is not as central to state politics in Europe as before, it is still an essential aspect of European culture and daily life for many people. Religious architecture dating from the Medieval era has been carefully preserved for religious and non-religious to experience. Additionally, migration has expanded ethnic and religious diversity in many parts of the continent, likely to increase over the following decades.