Did the Protestant Reformation lead to the Enlightenment?
Although it is not accurate to suggest that the Reformation led directly to the Enlightenment, we can nonetheless speak of it as being highly influential. For one thing, both movements displayed a profound distrust in authority being the measure of truth.
For Protestants, truth came from Scripture; individuals were encouraged to read the Bible for themselves in their own language. To the Catholic Church, this was highly subversive and dangerous. Traditionally, the Church had arrogated to itself the sole right to interpret the Bible. Bibles should not be made widely available to the people, they reasoned, especially not in their own vernacular; they might get ideas above their station, and all sorts of anarchy and chaos would be unleashed upon the world.
Thinkers of the Enlightenment had no such regard for the truth of Scripture. Nonetheless, they shared the Reformers' hostility toward the notion that if something were true, it was only because the Catholic Church said it was. What the philosophes sought to do was to secularize knowledge, taking it out the hands of the Church and other religious authorities and subjecting it to the only test that truly mattered: the standard of reason.
We can see this in relation to natural science, which the philosophes revered as the very paradigm of truth. The Church had often shown itself hostile to advances in scientific learning, most notoriously in the case of Galileo. The Enlightenment tended to regard the Church (not always fairly, it should be said) as a bastion of reaction, ignorance, and obscurantism, holding back the tide of intellectual progress to consolidate its position of secular and spiritual power. To this end, philosophes, such as Voltaire, strongly advocated the complete separation of church and state. The Church should confine itself wholly to spiritual matters, whereas secular concerns were the unique province of the state.
This idea was neither novel, nor particularly radical. The groundwork had already been laid by Luther more than two centuries earlier. In fact, one could go back even further in time and examine St. Augustine's doctrine of the two cities, the City of God and the City of the World. Luther's variant on Augustine was the doctrine of the two kingdoms. God ruled the world with both His "right hand" through the gospel, and His "left hand" through the work of the secular authorities. Princes and other magistrates were authorized by God to maintain peace and good order, even if it meant using the most brutal measures.
Indeed, one could argue that Lutheran theology encouraged a certain subordination of Church to State, stressing the absolute obedience of each subject to their earthly rulers, no matter how tyrannical they were. Although later Enlightenment thinkers such as Locke would have bridled at the very suggestion of such unthinking subservience to the state, philosophes like Voltaire had no such qualms. Voltaire, a devotee of "enlightened despotism," happily prostrated himself at the feet of tyrants such as Frederick the Great of Prussia and Russia's Catherine the Great. What mattered to him was that they were ostensibly devoted to the Enlightenment project's valorization of reason. Tyranny was perfectly acceptable so long as it was rational tyranny.
Unwittingly, Luther paved the way toward the Enlightenment in this regard. Secular rulers, in carrying out their temporal duties, were instruments of God's will. For many leading figures of the Enlightenment, secular rulers ought to be subject to the dictates of reason, which, for Deists such as Voltaire, meant much the same thing as God.
Indirectly, yes. The Protestant Reformation began in 1517 when Martin Luther, a disaffected German monk and professor of theology, nailed his 95 Theses to the door of the Wittenberg Catholic Church.
Luther was outraged by the Church's abuses of authority. He also believed that clergymen should not be the final and sole authorities on Scripture, but that all Christians should have access to the Bible (something which was made possible by Johannes Gutenberg in 1450 with the publication of the first printed Bible) and be able to interpret it.
Martin Luther's democratic stance on the Bible, as well as his rejection of the Church's ceremonial excesses, could be considered precursors for the Enlightenment. By questioning its morals and encouraging people to think (a bit) for themselves, he was undermining the Church's absolute authority. With Lutheranism, the Protestant sect of Christianity he created, he encouraged a simple and direct communion with God. Unlike Catholic churches, which were ornate and filled with examples of material wealth, Lutheran churches were practically bare aside from the pews and the pulpit. He also allowed members of the clergy to marry. He, in fact, was wedded to a nun, Katharina von Bora.
Luther's encouragement of simplicity, his individualistic thinking about Scripture, and his acceptance of natural human needs for sex and companionship were quite "modern." These ideas also anticipate Enlightenment thinkers' quests for knowledge, as well as their considerations of the "natural rights" of man (e.g., John Locke). Luther's emphasis on simplicity reminds one of Jean-Jacques Rousseau's idea that people became corrupted by civilization (of which the Church was a part) and should return to nature in order to lead lives of integrity.