In terms of its effect on the development of worldwide Christianity, the Protestant Reformation in Europe was perhaps the single biggest event (or rather, series of events) in Christian history since the Edict of Milan, if not the death and resurrection of Jesus.

The upheaval brought by the simple act of a German monk nailing a list of grievances to a church door ultimately rewrote the theology of the church, redrew the map of Europe, and revolutionized how billions of Christians engaged with their faith.

Of course, such massive and complex histories take hundreds of pages to tell thoroughly. (The “Complete” claim in the title might be a bit of an exaggeration.) But for anyone looking for a short introduction to the Reformation, this post will provide quick hits on the major players, places, events, and ideas that defined the movement and its legacy.

Precursors to the Protestant Revolution

The Protestant Reformation was the result of a spark that blew a powder keg which had been building for centuries. Here are some of the early figures who laid the groundwork for later reforms — and paid the price.

Peter Waldo (ca. 1140 – 1205)

Peter Waldo was a wealthy merchant from Lyons in southern France. When he was in his 30s, inspired by reading the Bible and Church fathers, Waldo sold all he owned, annulled his marriage, and began living in “apostolic poverty.” He called on the Catholic clergy to do likewise, preaching against church corruption and what he viewed as dogmatic inventions.

Many were inspired by his example, and formed a movement known as the Waldensians — but the Catholic Church was less fond of his ideas, and excommunicated the lot of them in 1184. Nevertheless, he continued preaching until his (apparently natural) death in 1205, and the Waldensians (having aligned themselves with John Calvin during the Reformation) persist to this day.

John Wycliffe (ca. 1328 – 1384)

John Wycliffe was an English theologian and philosopher who believed the Bible should be accessible to everyone, not just clergy, and translated it into English so that common people could read and interpret it for themselves.

Like Waldo, Wycliffe criticized the Catholic Church’s wealthy lifestyle and corruption, calling for a return to simplicity and adherence to the teachings of Jesus. His followers became known as Lollards, a movement that spread throughout England in the 14th century.

Despite opposition from the church, Wycliffe managed to preach relatively unmolested until his death of a stroke in 1384. But he was later declared a heretic in 1415 (a testament to his enduring influence) and his works were banned.

Jan Hus (ca. 1369–1415)

Jan Hus was a Czech Catholic priest and theologian who, through his followers the Hussites, was largely responsible for the Bohemian Reformation, a movement that flourished a century before Western Europe’s own Reformation and was a major inspiration for Martin Luther.

Hus himself was influenced by John Wycliffe’s writings. Like Wycliffe and Waldo, Hus objected to church corruption — particularly “simony,” the practice of selling holy things (such as indulgences) for profit.

He was excommunicated for his views in 1409 but remained active without much interference until 1414, when he was asked to defend himself to the Church at the Council of Constance. Though promised safe conduct, Hus was immediately arrested and imprisoned. When he refused to recant, he was finally burned at the stake on July 6, 1415.

Key Figures of the Reformation

The central figure of the Protestant Reformation was indisputably Martin Luther, with John Calvin close behind. Meanwhile, Thomas Cranmer emerged as the dominant voice in England.

Martin Luther (1483-1546)

Martin Luther came from humble beginnings, but through his immense conviction and courage he became the face of the Protestant Reformation.

Luther was a German monk and theologian who gradually became disillusioned with the Catholic Church’s corrupt practices, particularly the selling of indulgences. Indulgences were “passes” that people could buy from the church to allegedly decrease their time in purgatory. Luther made his views known by nailing his “Ninety-Five Theses” to the door of the Castle Church in Wittenberg.

Luther was a towering intellect and complex figure. Among his many exploits, he translated the Bible into German vernacular (publicly wishing he could expunge the books of Revelation and James); composed an entire hymn book; married a former nun; disseminated violent polemics against Jews, Catholics, and other Christians with whom he disagreed; and infamously claimed to have hurled his feces at the Devil.

He traveled widely throughout Europe, particularly around Germany, throughout his life. But his health gradually deteriorated throughout the 1530s, and he died finally of a stroke in his home in Wittenburg in 1546.

John Calvin (1509-1564)

John Calvin was a French lawyer and, later, theologian and pastor whose influence on the Reform movement was second only to Martin Luther.

Unlike Luther, Calvin was not ordained and in fact seems not to have been particularly religious in his early life but underwent a kind of conversion sometime around his 30th birthday. Soon after, he began work on what would become his magnum opus, the Institutes of the Christian Religion.

Calvin’s objections to the Catholic Church were more theological in nature and less ecclesiastical than Luther’s — though he did deny the legitimacy of the Pope and any literal presence of Christ in the Eucharist.

His principal arguments revolved around the absolute sovereignty of God and “total depravity” of humankind. In other words, all people deserved damnation and could do nothing whatsoever to affect their salvation, but God predestined a certain “elect” group to be saved.

Calvin was forced to flee his native France when religious violence broke out, and ultimately settled in Basel, Switzerland, which had become a Protestant haven. He rose to political influence in the city, and though he traveled to promote his ideas throughout Europe, he made his permanent home there until his death in 1564.

Thomas Cranmer (1489 – 1556)

The Reformation in England was peculiar in that, unlike in Luther’s Germany or Calvin’s Switzerland, it began not because of theological or doctrinal disputes, but simply because King Henry VIII (r. 1509-1547) wanted a divorce, and the Pope wouldn’t give him one.

Into this predicament stepped Thomas Cranmer, a priest and liturgist whose early motives are not altogether clear. He seems to have been sympathetic to Luther’s views — but more pertinently, he ascribed to a position of “royal supremacy,” which held that the King (rather than the Pope) should oversee all matters of the church in his realm. This view may have been a largely practical one, given the geographical distance between England and Rome, which made communication between them slow and difficult.

Whatever the case, Cranmer helped Henry annul his marriage and develop statutes governing the doctrine and liturgy of the Church in England. The process was slow at first. But after Henry’s death, when Edward VI (r. 1547-1553) took the throne, Cranmer received more license to implement his vision. He completed the Book of Common Prayer in 1549, which served as a complete liturgy for the new church as well as a form of promulgating Cranmer’s Protestant views on the Eucharist, priestly celibacy, and other issues.

But Cranmer’s fortunes changed when the Catholic Queen Mary (r. 1553-1558) assumed power, fired all the reformers, and reinstituted Catholic clergy. Cranmer was charged with treason in November 1553 and sentenced to death, but instead remained in prison for nearly two years until he was given a chance to recant. Recant he did, professing full allegiance to the Pope and all Catholic teachings — but although Rome was satisfied, Mary was not, and determined to execute him anyway on March 21, 1556.

Immediately before being burnt at the stake, Cranmer was given the chance to express his remorse before God and man once more from the pulpit using a prepared statement — but at the last moment, he dramatically broke script, repudiated his recantations, and declared the Pope Antichrist.

Luther’s Ninety-Five Theses (1517)

The event that kickstarted the Protestant Reformation in full was the 95 Theses of Martin Luther, which he nailed to the door of the Castle Church in Wittenberg, Germany on October 31, 1517.

The Theses mainly revolved around a very particular issue: the sale of indulgences, documents sold by the Catholic Church that promised the holder a shortened stint in purgatory. Luther objected to the practice on both ethical and theological grounds, saying that the Pope had no power over purgatory, if indeed there is such a thing, and that it is the duty of every Christian to repent. There is no shortcut to salvation.

Luther intended the document to initiate a dialogue rather than a revolution — but of course that was exactly what happened. Almost immediately, the Theses became widely distributed through the new printing press — and hotly debated.

The Diet of Worms (1521)

Luther was called to recant his views at the fantastically named Diet of Worms (a “diet” was essentially a parliamentary gathering of the Holy Roman Empire, and Worms was where this one was held) in April 1521. Luther apologized for his occasionally harsh tone, but not for the content, which his conscience would not permit him to deny.

Here he made his famous declaration: “Here I stand. I can do no other. God help me, amen.”

Somewhat miraculously, Luther was allowed to leave the diet in peace. But a month later, the Holy Roman Emperor Charles I issued the Edict of Worms, which declared Luther a heretic and enemy of the state, banned his writings, and permitted any citizen to kill him on sight.

No one ever did, though, and Luther died of natural causes some 15 years later. By then, the Protestant Reformation was in full swing.

The Five Solae (or Solas)

The “Five Solae” (the Latin plural of “sola”) are a collection of theological statements expressing a distinction in Protestant thought against Catholic tradition. Though these statements were never made in such a format during the Reformation itself, they have come to succinctly represent its principal claims.

Of course, like all brief summaries, they paint with a broad brush, and overlook distinctions between Lutheranism, Calvinism, Anglicanism, and other Protestant movements. But they are helpful for understanding the Reformers’ overall disagreements with Catholicism.

Sola Scriptura (Scripture Alone)

Scripture alone is the authority on Christian doctrine. Often considered the central “sola” or principal of the Reformation, “sola scriptura” contrasts the Catholic (and Orthodox) view that church tradition — through councils, creeds, decrees, and other teachings — is intertwined with Scripture as the source of Christian truth.

Sola Fide (Faith Alone)

Justification by faith alone. Justification (how we are made righteous and cleansed of sin — not technically the same as salvation, which Christ granted to all people at Calvary, but often conflated) happens simply through trusting in Jesus’s sacrifice for us on the cross. This is in distinction to the traditional Catholic teaching that justification requires human participation in the acceptance of Divine Grace.

Sola Gratia (Grace Alone)

Salvation through grace alone. Closely related to sola fide, sola gratia means God’s free grace is sufficient for our salvation. There are no “good works” or charity we can do to make ourselves more worthy. (In fact, this view is shared by most Christian denominations, including Catholicism; it’s the justification part where they differ.)

Solus Christus (Christ Alone)

Christ alone mediates between God and humanity. Priests are not a separate class able to intervene on behalf of laypeople — only a direct relationship with Jesus Christ provides access to God the Father. People should therefore confess to God directly, not to priests, who cannot offer absolution.

Soli Deo Gloria (Glory to God Alone)

God alone deserves the glory of worship. This principle rejects any veneration of Mary, the saints, and angels. They may be worthy of admiration — but only because the Holy Spirit made them so. They are not worthy of devotion.

Major Centers of the Reformation

The Protestant Reformation began in Germany, but quickly spread to Switzerland, then to England and elsewhere in northern Europe. Meanwhile, southern Europe remained firmly Catholic.

Germany

Germany — then called the Holy Roman Empire — was the epicenter of the Reformation from the moment Luther nailed his Theses to the door.

There were two reasons why Luther succeeded where Hus had failed a hundred years earlier: the printing press, and the interest of the German princes.

Luther’s ideas spread — and caught on — quickly thanks to the printing press. Even once outlawed, it was relatively easy to circulate them in secret. And among Luther’s sympathizers were a number of German princes and nobles who resented the Catholic Church’s influence in their government.

In addition to Luther, scholars like Philip Melanchthon (who was instrumental in systematizing Luther’s sometimes scattered thinking into a cohesive theology) and various evangelical preachers helped the new movement spread among the educated, priestly classes as well as disaffected commoners.

Switzerland

Switzerland was one of the first places to establish itself as a Protestant haven, thanks in large part to the influence of Ulrich Zwingli.

Sometimes referred to as the “Third Man of the Reformation” (after Luther and Calvin), Zwingli had independently arrived at many of the same conclusions as Luther regarding the need for church reform. His efforts in Zurich and Basel laid the groundwork for the Swiss Reformation, which would later merge with Calvinism to form the Reformed tradition.

England

As discussed above, England’s Reformation began quite differently than on the continent. Initially the English Reformation seemed like a cynical, politically expedient opportunity seized by Henry VIII to annul his marriage after gazing across the Channel at the events unfolding in Germany and Switzerland. But it soon took on its own distinct flavor thanks to the vision of Thomas Cranmer and Thomas Cromwell.

While Cranmer advanced the theological and liturgical development of the new Church of England, Cromwell oversaw its ecclesial establishment by dissolving the monasteries and abolishing images of Mary and the saints. (He later fell afoul of the king, though, and was executed for unclear reasons along with other Protestants and Catholics alike.)

Things became complicated in England because of dueling influences of traditionalist Catholics, on the one hand, and radical Puritans on the other. Puritans, strongly influenced by Calvin, wanted to rid the church of all “papist” influence. The Church of England wavered between these influences, sometimes violently, but overall tried to strike a balance between traditional liturgy and reformed theology.

Catholic Strongholds

While the Reformation raged in western and northern Europe, eventually extending up through Holland and Scandinavia, its influence was much milder in the southern European countries around the Mediterranean.

There are many complex reasons for this division, which scholars continue to debate — but here are a few major factors:

• Italy was the seat of Papal power and had been for centuries. One way of understanding the spread of Protestantism simply comes down to distance from Rome, which dominated much of Italy.
• Spain and Portugal were also very close to Rome, both geographically and politically. The Spanish Inquisition commanded almost unchecked power in Iberia at the time, and was infamously ruthless in stamping out any whiff of heresy in the region.
• France proved contentious and was one of the bloodiest theaters of the Reformation, with millions killed during the French Wars of Religion in the late 16th century. In the end Catholicism (barely) prevailed, and French Protestants (known as Huguenots) went underground or fled by the thousands for England, Switzerland, or elsewhere.
• Poland-Lithuania remained relatively neutral throughout the Reformation. The Catholic king chose to tolerate Protestantism and even codified religious freedom in 1573 — long before most other Western countries. In practice, however, Protestants experienced intermittent persecution and distrust until at least the 18th century.

The Radical Reformation

Almost as soon as the Reformation coalesced under leaders like Luther and Calvin, it spawned splinter groups who felt those leaders didn’t go far enough in their rejection of Catholic influence.

Known collectively as the Radical Reformation, these smaller groups felt that the “Magisterial Reformation” (as Luther’s and Calvin’s movements had become known) was simply replacing the Catholic elite with a new elite. Instead, they rejected any larger church organization at all, and insisted that anyone who professed belief in Jesus Christ (and practiced his teachings) could minister in his name. This, they believed, was how the original church of the apostles was structured.

Because of this stringent commitment to the “original” church, the radical reformists typically took extreme (or “radical”) views on many issues — some of which proved influential on the wider Reformation. These included Biblical literalism, millenarianism, believer’s baptism (rather than infant baptism), shared communal possessions, strict nonviolence, and sometimes gender equality.

But despite their influence, since these “radical” groups objected equally to dominant Catholic and Protestant churches, they were often persecuted by both.

Anabaptists

The largest and most enduring of the Radical Reformation sects was the Anabaptist movement, which organized in 1527 around a statement of faith that strongly emphasized the importance of personal commitment in matters of faith and rejected any state involvement in religion.

Anabaptists practiced the believer’s baptism and strict adherence to the precepts of the Sermon on the Mount, including pacifism and forgiveness.

Today, Mennonites, Amish, and other groups are direct descendants of the Anabaptists. Though Baptists have a different lineage (from Rhode Islander Roger Williams), they have many shared beliefs.

The Catholic Counter-Reformation

As Luther and Calvin’s influence quickly gathered steam and it became clear this was not a matter that could be dealt with as efficiently as Wycliffe and Hus, the Catholic Church came together to articulate a united response to the Protestant Reformation.

It was a complicated project: the church was forced to acknowledge and address the issues that had generated such intense and widespread rebellion, while also affirming and defending its traditional stances. It had to simultaneously consolidate its power and eradicate corruption.

Council of Trent (1545 – 1563)

The Catholic Church undertook its reforms and recommitments in true Catholic fashion: through more than two dozen meets over a period of nearly 20 years (nobody can say the Church acts too rashly).

The Council of Trent was wide-ranging in scope, reexamining nearly every aspect of Catholic doctrine and liturgy. In each instance, the Church released a document stating its doctrine and condemning the (typically Protestant) alternatives.

Some of the topics the council addressed include:

• The Bible: The Church, and not “every believer,” has the final say in the interpretation of Scripture. The Latin Vulgate is the official Bible of the Catholic Church, and the Apocrypha are equal canon to all other books.
• The Church: Church tradition, through apostolic succession and the primacy of Peter, has equal authority to the Bible.
• Faith vs. Works: “Faith alone” is insufficient; human effort is necessary to accept God’s free grace.
• Eucharist: The Lord’s Supper is not symbolic but is transubstantiated (literally changed in substance) into the body and blood of Jesus.
• Purgatory and Indulgences: The doctrine of purgatory was affirmed, as was the validity of indulgences, although the Church decreed that indulgences could not be sold for money.
• Mary and the Saints: Veneration of Mary, the saints, and religious relics was also affirmed, as was the use of religious art for devotional purposes.

The Fallout: Political and Religious Upheavals

The popularity of Protestant grew quickly — but by no means peacefully. In fact, the decades following the 95 Theses were among the bloodiest in Europe’s history until the 20th century.

Though remembered as the European Wars of Religion, historians acknowledge the motive for most of these conflicts was only partially religious, and was also wrapped up in all the standard causes: land grabs, succession struggles, self-rule, etc.

Some of the bloodiest include:

• Peasants’ War (Germany, 1524): It lasted only a year, but saw over a hundred thousand peasants (mostly Anabaptists) killed, as well as some Lutheran and Catholic landowners.
• French Wars of Religion (1562-1598): Between 2-4 million people died in this struggle between Catholics and Calvinist Huguenots in France; it finally ended with the Edict of Nantes in more or less of a draw.
• Thirty Years War (Germany, 1618-1648): Perhaps the most devastating conflict in European history until World War I, as many as 8 million people died in this struggle that began over how to divide the territories of the Holy Roman Empire into Lutheran, Calvinist, and Catholic sections, but then grew into questions of independence and self-rule across western and northern Europe.

In the British Isles, struggles were ongoing throughout this period as power was traded between Anglican, Catholic, and Puritan leaders, who often dispatched their predecessors and asserted their rule violently.

Legacy of the Reformation

The Protestant Reformation redrew the map of Christianity across the Western world. Later, through a combination of evangelical missions and colonial rule, it would also come to define much of the Christian faith around the globe.

Today, over one-third of Christians worldwide follow some form of Protestantism — second only to Catholicism, which still commands half of Christian adherents.

Protestant Denominations Today

The major streams of the Reformation — Lutheran, Calvinist (Reform), and Anglican — still represent the majority of Protestants, though they have since splintered into ever-increasing smaller denominations.

Lutheranism

Lutheranism today comprises around 85-90 million believers, mostly in the Lutheran World Federation. It remains popular (if declining) in Germany and Scandinavia, as well as the United States and parts of Africa (e.g., Ethiopia and Tanzania). Lutheranism retains a “high-church” liturgy similar to Catholicism, but with an emphasis on the “five solae,” especially faith, grace, and Scripture.

Calvinist/Reformed

The Reformed tradition derived from Calvin experienced the widest spread — and the most division — especially after intermingling with other streams of thought, especially in England. Its most direct descendants are the Reformed Churches, Presbyterians, and Congregationalists (formerly Puritans), which together count roughly 65 million members.

Anglican Communion

Thanks to England’s enormous colonial activity, Anglicanism became the third-largest individual communion of churches in the world (after Catholicism and Eastern Orthodoxy), with over 85 million members. Its churches still use Cranmer’s Book of Common Prayer, though it has since gone through several rounds of revision.

Other Protestant Denominations

Various groups of English dissenters grew out of a hodgepodge of Calvinist, Anglican, and Radical influence, as well as individual claims to direct revelation. The largest of these today is Baptism (around 75 million, themselves divided into many smaller churches), which couples Calvinist thought with Anabaptist influence.

Second is Methodism, with roughly 40-60 million members, which broke from the Anglican church through John Wesley’s unique theology centered around sanctification.

Anabaptists, though small in number, still exist primarily through the Mennonite World Conference, which includes about 2 million members.

Although not directly derived from the Reformation, Pentecostal and nondenominational churches would not have been possible without their Protestant forebears, as they trace their lineage back to them through Methodism and generally conform with the five solae. Pentecostalism emphasizes direct communion with God through the Holy Spirit. Though not a unified movement, affiliated churches claim some 280 million adherents.

The Reformation and the Bible: Making God’s Word Accessible

Aside from the breakup of Catholic hegemony through the creation of many new denominations, perhaps the most enduring practical effect of the Reformation was how it changed people’s relationship to the Bible.

Vernacular Translations and the Printing Press

Prior to the Reformation, most European Christians engaged with the Bible only when they heard it read in Mass — in Latin, a language few of them understood. The extent of their religious literacy would have been whatever they could glean from the artwork adorning their local churches and cathedrals.

Three things began to change that:

1. First, Luther and Calvin emphasized Scripture as the sole source of divine revelation and Christian truth.
2. Second, because of that, they advocated for (and Luther personally conducted) translation of the Bible into the actual spoken languages of the people.
3. And third — crucially — the advent of the new printing press made those new translations widely available in a way that had never before been possible.

Rediscovery of Hebrew and Reappraisal of the Apocrypha

This new focus on Bible reading didn’t just change how accessible the Bible was — it also changed how we think about canon. (Canon is the official collection of books determined to be divinely inspired and included in Scripture.)

When Protestants chose to translate the Bible into their native languages — from Luther’s German Bible to French Olivétan Bible to the English Geneva Bible and, later, King James Bible — they frequently chose to go back and translate from the original Hebrew Old Testament and Greek New Testament, rather than the Latin Vulgate that had been in use by the Catholic Church for over a thousand years.

When they did this, they found that the Hebrew Bible was missing quite a few of the books that were included in the Vulgate’s Old Testament. Furthermore, the Jewish writers of the New Testament era apparently didn’t approve or quote from these books. So the translators separated them into a secondary or even “false” category between the testaments — or left them out altogether.

We now know these books as the Apocrypha or Deuterocanonical books. They remain in use in Catholic and Orthodox Bibles — but the Reformers rejected them, and they are no longer found in Protestant Bibles.

Conclusion: The Enduring Influence of the Reformation

The Protestant Reformation reshaped Christianity throughout Europe and, ultimately, across the globe through the bold actions of figures like Martin Luther and John Calvin. Though precursors had been laying the groundwork for centuries, it was Luther’s “Ninety-Five Theses” that became the “shot heard ‘round the world,” and his subsequent courage at the Diet of Worms marked a point of no return for the movement.

Meanwhile, Calvin’s theological contributions (and use of the printing press) expanded the conversation beyond Germany and drew even further away from traditional liturgies, while England’s separation from Catholicism paved the way, through its later colonial efforts, for the massive spread of Protestant ideas worldwide.

Over decades of heated and often bloody struggle, the Reformation not only redefined Christian thought and worship but also transformed societies and governments. Its legacy endures in the ever-diversifying expressions of Christianity today — not least in how we engage with the Bible.

Want to go deeper into how the theology of the Reformation influences our understanding of the Bible today? Good news: not only is there a Study Bible for that, but there are several — and they’re available on Bible Gateway Plus for only a few dollars a month after free trial!