The reformers did not set out to create religious freedom, mass literacy or the modern state. Luther, Calvin and the bishops at Trent all believed a Christian ruler should protect true religion and suppress error. Yet the Reformation changed Europe in ways none of them intended, and historians still argue about how far its consequences reach.

From persecution to toleration

The first arguments for toleration came from those who lost, and from a few who refused to accept the burning of opponents. After Servetus died, the humanist Sebastian Castellio protested that killing a heretic does not defend a doctrine; it only kills a man. In his own words: "To kill a man is not to defend a doctrine, but to kill a man." His reply to Calvin circulated in manuscript and was printed only in 1612.

Elsewhere toleration grew from political necessity. In Transylvania the Diet of Torda in 1568 allowed preachers of several confessions to preach freely. In the Warsaw Confederation of 1573, Polish nobles pledged to keep peace among themselves despite differences in religion, at a time when much of Europe was burning heretics. In the Dutch Republic, and later in Rhode Island, founded by Roger Williams in 1636, liberty of conscience became a principle as well as a convenience. John Locke's Letter Concerning Toleration of 1689 gathered these strands into a classic argument.

Hard truths

An honest account must include the age's cruelties. Catholic and Protestant authorities executed thousands of dissenters, Anabaptists most of all. The persecution of supposed witches, which killed perhaps 40,000 to 60,000 people across Europe, peaked roughly between 1560 and 1630; witch trials struck Catholic and Protestant lands alike, worst of all in parts of the fragmented empire. And Luther, who early in his career urged kindness toward Jews in the hope of converting them, turned on them in old age. In 1543 Luther urged rulers to burn synagogues and expel Jews, words that later German antisemites, including the Nazis, eagerly reprinted. Lutheran churches have since formally repudiated these writings.

Reading and schooling

Protestants wanted believers to read Scripture and know the catechism, and Luther urged towns to found schools for boys and girls. The effect was strongest where church and state pushed together. Sweden's church law of 1686 required reading tests for every household, through regular parish examinations that recorded each person's progress, and by the late 1700s most Swedes could read, though far fewer could write. Catholic reformers built schools too, through the Jesuits and the teaching orders for girls. Economists Sascha Becker and Ludger Woessmann studied Prussian census data from 1871 and found that Protestant areas had higher literacy, which may explain much of their economic edge. Their work offers an alternative to Max Weber's famous argument that a Protestant work ethic drove prosperity.

Church and state

Almost everywhere, the Reformation strengthened rulers. Protestant princes took control of church property, appointed church officials and wrote church ordinances. Catholic rulers won concessions from Rome in return for loyalty. Historians Heinz Schilling and Wolfgang Reinhard called the process confessionalization: Catholic, Lutheran and Reformed states all used religion to discipline subjects and build state power, through catechisms, visitations, church courts and parish registers. Critics say the thesis overrates how obedient ordinary people were, but it explains why the three confessions, so opposed in doctrine, often looked alike in practice.

The big argument

Was the Reformation a liberation or a fracture? Protestant tradition long told a story of freedom: freedom of conscience, the Bible in every language, resistance to tyranny. Catholic tradition stressed the loss of unity and the bloodshed that followed. A recent and much debated version comes from the historian Brad Gregory, who argued in 2012 that unresolved doctrinal disputes unintentionally pushed public life toward secularism, an outcome no reformer wanted. Critics reply that he underplays the coercion of the medieval church and the real gains of pluralism. Either way, one lesson lasted. Europeans learned, at terrible cost, that sincere people could read the same Bible and reach different conclusions, and that a society could survive only by protecting the consciences of those it thought mistaken.

Worked example: a petition for conscience

Imagine a Mennonite congregation in a Dutch town around 1620 asking the magistrates for permission to meet for worship. They cannot claim a right; no law gives them one. They argue instead that they pay their taxes, keep the peace, obey every lawful command except oaths and bearing arms, and harm no one by their prayers. The magistrates, Reformed themselves, weigh public order, trade and their own consciences, and allow meetings in a private house with no sign outside. Arrangements like this, repeated in many places, show how toleration often grew: not from a grand theory but from practical bargains that later thinkers turned into claims of right. They also show why rights matter. What depends on a magistrate's favor can be taken away, as the Huguenots of France learned in 1685.