A dispute that became a public debate
In 1517, the Wittenberg professor Martin Luther circulated a set of Latin propositions, the Ninety-five Theses, criticizing the way indulgences were being sold. Whether he nailed a copy to a church door, as the familiar story says, is debated among historians, and the evidence for that dramatic picture is thin. What is better supported is that the theses were soon printed, in Latin and then in German, in several cities, and that the matter quickly reached readers far beyond the university.
This is the key point about printing and the Reformation. Disputes among theologians had happened before, and earlier reformers such as Jan Hus had also attracted followers. What was different in the 1510s and 1520s was that there were now many print shops able to turn a text into hundreds of copies within days or weeks, and a growing audience ready to buy.
Luther and the pamphlet
Luther turned out to be unusually well suited to the new medium. He wrote in plain German as well as Latin, and he favored short, direct works. Pamphlets, usually only a few sheets, were cheap to print and easy to carry. Within a few years, his writings made up a large share of the German-language works printed in the Holy Roman Empire, according to commonly cited estimates, and local printers found them a reliable seller.
Wittenberg itself became a printing center. The artist Lucas Cranach the Elder, who lived in the town, produced woodcut portraits and illustrations, and printers such as Hans Lufft produced editions of Luther’s translations. Luther’s German New Testament appeared in 1522, and a complete German Bible in 1534. Earlier German Bibles existed, but his version circulated widely and is often credited with influencing the written language.
Printed images mattered as much as text. Woodcuts showing the pope as an enemy or the reformers as heroes reached those who could not read, or who could follow a picture and a caption. Hymns were printed as songbooks and sheets, so the movement could be sung as well as read.
Both sides used print
It would be wrong to portray printing as a tool only for reformers. Catholic writers and printers also produced replies, sermons, catechisms and polemics, and rulers on every side tried to use print for their own purposes. Authorities attempted to control it by licensing and banning books. The Catholic Church issued its first Index of Prohibited Books in 1559. Such lists were difficult to enforce, since printers could move, print anonymously or invent a false imprint.
Print also fed disagreements among Protestants. Debates between Luther and other reformers, and between various groups about baptism, communion and authority, were conducted in pamphlets. During the German Peasants’ War of 1524 to 1525, printed grievances, such as the Twelve Articles, circulated widely. Luther himself condemned the revolt in print. In other words, the same technology that carried one movement carried its critics and its rivals.
William Tyndale and vernacular Bibles
Printing also aided translations of scripture elsewhere. William Tyndale’s English New Testament was printed on the Continent, with a printing at Worms in 1526, and smuggled into England, where authorities tried to suppress it. He was executed in 1536. His wording influenced later English translations. The example shows how print made forbidden texts hard to contain, even though it did not guarantee that they would survive or be tolerated.
Printed texts and scientific debate
The press also carried scientific and scholarly arguments, which sometimes crossed paths with religion. Desiderius Erasmus’s printed Greek New Testament of 1516 gave scholars a text to compare and criticize. In 1543, Nicolaus Copernicus’s book on the movement of the planets was printed at Nuremberg, and Andreas Vesalius’s anatomy text was printed at Basel with detailed illustrations. Because these books existed in many copies, scholars in different places could read, test and dispute them, instead of relying on single manuscripts.
Practical and esoteric subjects were printed too, including medical manuals, navigation guides and works connected with alchemy history. In the following century, publications such as Robert Hooke’s Micrographia of 1665, based on observations through early microscopes, showed how printing helped turn individual observations into shared knowledge. Printed illustrations were crucial there, since a drawing could be reproduced far more consistently than by copying by hand.
The relation between religion and science in this period was complicated. Some religious authorities opposed new astronomical claims, while many scholars were also clergy or deeply religious. Printing did not settle these arguments. It made them more visible and permanent.
Weighing the claim
It is tempting to say printing caused the Reformation. Most historians are more careful. Political rivalries among German princes, local grievances, a long tradition of criticism of the church and Luther’s own abilities all contributed. What printing did was change speed and scale: it made it harder to suppress an idea once it had appeared, and it gave authors a way to address strangers directly.
The spread of literacy was uneven, and the share of people who could read was limited in the early 1500s. Preaching, reading aloud and pictures carried printed arguments to many who could not read for themselves. The press was a powerful amplifier, but it worked through existing networks of towns, churches, schools and trade.