Key takeaways
- Wikipedia describes the Reformation as a 16th-century theological movement in Western Christianity that challenged the papacy and marked the beginning of Protestantism.
- It is usually dated from Luther's Ninety-five Theses of 31 October 1517, though Calvinist historians often date it from Zwingli's preaching in 1516; its end date is even more disputed.
- The Stanford Encyclopedia of Philosophy says the nailing of the theses to the church door is legend and that Luther seems to have sent them to Archbishop Albrecht of Mainz.
- Luther was excommunicated on 3 January 1521 and refused to recant at the Diet of Worms in April 1521.
- The Peace of Augsburg of 25 September 1555 reaffirmed cuius regio, eius religio, but allowed princes to choose only between Catholicism and the Augsburg Confession.
- Wikipedia puts deaths in the consequent European wars of religion at between seven and seventeen million.
The Protestant Reformation was a sixteenth-century theological movement in Western Christianity that, in Wikipedia's summary, posed a religious and political challenge to the papacy and the authority of the Catholic Church hierarchy, and marked the beginning of Protestantism. It is usually dated from Martin Luther's Ninety-five Theses of 1517. What it became — several rival churches, a Catholic response and decades of war — was not what anyone set out to create in 1517.
Indulgences for a basilica in Rome
The trigger was a fundraising campaign. Wikipedia explains that Pope Leo X (r. 1513–1521) wanted to complete the new St Peter's Basilica, begun in 1506, and in 1515 announced a new plenary indulgence to pay for it. Albert of Brandenburg supervised the sale in Germany, and the Dominican friar Johann Tetzel used what Wikipedia calls unusually aggressive marketing; a slogan attributed to him claimed that "as soon as the coin into the box rings, a soul from purgatory to heaven springs".
Luther was then a theology professor at the University of Wittenberg in Saxony. The Stanford Encyclopedia of Philosophy (SEP) traces his doubts about indulgences to his reading of mystical authors, and notes that earlier in 1517 he had already written a more intellectually radical set of theses, the Disputation Against Scholastic Theology.
31 October 1517: two accounts of one day
Sources agree on the date and differ on the scene.
- Wikipedia says that on 31 October 1517 Luther wrote to Albert of Brandenburg, complaining that indulgence preachers were deceiving the faithful, and attached the Ninety-five Theses. It describes the famous nailing to the Wittenberg castle church door as "allegedly" happening, but adds in a note that the story is "quite probable", because Wittenberg academics regularly published disputation papers that way — even though it was first mentioned years afterwards.
- The SEP is blunter: "according to legend" Luther nailed the theses to the door, but "in reality it seems he merely sent them" to the archbishop; it was printed copies that made them circulate.
Both are reputable, and they weigh the same evidence differently. That is a small, clean example of the problem discussed in when two sources disagree. What neither disputes is that print turned an academic disputation into a public controversy — the subject of the printing press and its impact.
From a friars' quarrel to the Diet of Worms
Rome was slow to take it seriously; Wikipedia reports Leo calling it "a quarrel among friars". The pace then picked up:
| Date | Event (as given by Wikipedia and the SEP) |
|---|---|
| October 1518 | Cardinal Cajetan meets Luther at Augsburg |
| 15 June 1520 | Bull Exsurge Domine condemns 41 of Luther's theses, with 60 days to recant |
| 1520 | Treatises including To the Christian Nobility and On the Babylonian Captivity of the Church |
| 3 January 1521 | Excommunication published |
| April 1521 | Luther refuses to recant at the Diet of Worms |
| 4 May 1521 | Staged abduction to the Wartburg, where he translates the New Testament into German |
At Worms, the SEP notes, it is doubtful he actually said "here I stand, I cannot do otherwise"; the recorded statement says he was bound by Scripture and that his "conscience is captive to the Word of God". The Edict of Worms then declared him a heretic and outlaw, and Frederick the Wise of Saxony protected him. Separating the remembered line from the recorded one is the method described in how we know what historical figures did.
Many Reformations, not one
Wikipedia stresses that the sixteenth-century term covers four major movements: Lutheranism, Calvinism, the Radical Reformation and the Catholic Reformation or Counter-Reformation. Since the late twentieth century, it notes, historians often use the plural "Reformations".
- Zurich. Huldrych Zwingli claimed he had preached the Gospel from 1516, "long before anyone in our region had ever heard of Luther", and came to prominence over a Lenten sausage meal in 1522.
- Geneva and beyond. John Calvin developed, with Zwingli, the Continental Reformed tradition; within a Reformed framework, Thomas Cranmer and John Knox led the Reformations in England and Scotland.
- The radicals. Anabaptists sought a return to the practices of early Christianity; Wikipedia quotes Carter Lindberg calling the German Peasants' War "a formative experience" for many of their leaders.
- England. Henry VIII, once named Defender of the Faith for a book against Luther, broke with Rome over his annulment. The Act of Supremacy (1534) made him "only supreme head of the Church of England", and Wikipedia records that 65 of about 400 defendants who refused the loyalty oath were executed — about one in six (16.3%).
Trent and the Catholic answer
The papacy responded in council. Wikipedia states that Pope Paul III convoked the Council of Trent, which met in sessions from December 1545 to 1548, 1551 to 1552 and 1562 to 1563, dealing with the Creed, the sacraments, justification and the training of priests in diocesan seminaries. Historian Massimo Firpo, Wikipedia notes, distinguishes a "Catholic Reformation" focused on pastoral renewal from a "Counter-Reformation" of defending orthodoxy and repressing dissent.
Augsburg in 1555, and the problem it left
In the Holy Roman Empire, the settlement was political. After war between the emperor and Protestant princes, the Peace of Augsburg was concluded on 25 September 1555. It reaffirmed cuius regio, eius religio — the ruler's religion would be his territory's — but, as Wikipedia notes, the Estates could choose only between Catholicism and the Augsburg Confession. Calvinists were left out.
That gap matters for dating the end of the Reformation, which Wikipedia calls "even more disputed" than its start. The usual candidates are 1555, 1618 and 1648. Counted from 1517, those give an era of 38, 101 or 131 years. The last two mark the outbreak and end of the Thirty Years' War, which has its own guide. Wikipedia puts deaths across the European wars of religion at between seven and seventeen million — a range of ten million, which shows how uncertain the figures are.
Exploring the period
The cultural background is in what was the Renaissance. World History Timeline Sim, our own app, organises major events by year, era, region and category, which helps keep Wittenberg, Zurich, London and Trent in one frame. A choice made in its Time Travel Mode produces a simulated chain of effects, which is alternate history and should not be confused with the record. The store listing frames the app as a companion to coursework rather than a replacement for it; for 1517 itself, the Ninety-five Theses and the sources cited above remain the place to check. It costs nothing to install and carries ads and optional in-app purchases; see also education and brain apps.
Good to know
Frequently asked questions
What started the Protestant Reformation?
Did Luther really nail the Ninety-five Theses to the church door?
Why did Henry VIII break with the Pope?
What did the Peace of Augsburg of 1555 decide?
Sources
- Reformation (opens in a new tab)Wikipedia — accessed
- Martin Luther (opens in a new tab)Stanford Encyclopedia of Philosophy — accessed
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