One persistent emphasis is on the commercial aspects of books. Pettegree begins with the pre-existing book market and continuities with the manuscript world, before describing the origins of printing. Exploiting technological innovation in the printing process itself, however, required accompanying business and commercial innovation. Most early printers failed, and printing was a capital-intensive and highly competitive business. (Around half the cost of a book was in the paper.)
"Fifty years after Gutenberg's triumph print was an inescapable part of the book world. But it was still a world catering mostly for a moneyed and restricted readership, based on a familiar and rather conservative range of texts."
The broader spread of books involved the creation of new markets, most notably for vernacular works, and of distribution and sales networks to serve them. There were significant "network effects" in all of this, and one result was the concentration of printing in a few major centres, towards the end of the 16th century in cities such as Paris, Lyon, Antwerp, Venice, Basel, Augsburg, and Leipzig; the annual Frankfurt book fair was the highest profile sales event.
A second ever-present theme is the intimate involvement of books in the religious and political conflicts of the era. Here Pettegree describes the spread of Protestant ideas along with books and the extent to which the printers of Wittenberg and Geneva existed in symbiosis with Luther and Calvin; and also the later Jesuit use of printing. The search for order in a troubled world also resulted in a wide range of works on political philosophy, often part of ongoing debates. As a kind of foil to all of this, apolitical and non-confessional "emblem books" — which sound like the crosswords or sudoku of early modern Europe — were also popular.
The religio-political and the commercial often interacted. Papal censorship placed Italian printers and booksellers at a disadvantage, for example, while London's near-monopoly of printing within Britain had both commercial and political foundations. Many individual printers ended up losing their businesses, or worse, for taking the wrong side or printing the wrong books; others were forced to relocate or had their entire output banned in some jurisdictions because of a few books or authors.
Interspersed with these broad themes are chapters dealing with more specialised topics. Printed pamphlets had a key role in spreading the news, though this was again political, with successful battles being much more widely publicised than defeats. Printing helped spread the great vernacular romances and the development of reading as a polite recreation, and the printing of music soon became an important speciality. And the spread of books and growth in literacy helped create a demand for education, which in turn drove the demand for school texts.
Books on science and exploration, notably on astronomy and cosmology, geography and botany, often involved extensive and expensive illustrations; and even high-status works such as these began to appear in vernacular languages. Medical publishing was dominated by the rediscovery and revival of ancient texts, above all Galen, but a broad range of works show books were not limited to "learned medicine" but played a key role in the status hierarchies of medical practitioners.
A final chapter considers the construction and destruction of libraries, with some examples of the fates of personal collections. Not just here but throughout The Book in the Renaissance Pettegree emphasizes the distortions and biases in what survives — whether actual books or records of them such as the inventories of failed businesses. He tries to give some feel for the "the lost world of posters, pamphlets and pictures", which is how many if not most publishers actually made money, doing relatively simple one-off jobs for governments or institutions.
A historian of early modern Europe, Pettegree provides considerable context for all of this. On the large scale, for example, he doesn't assume any detailed knowledge of the political and religious conflicts of the Reformation, and on a smaller scale he includes brief explanations of specialised topics, for example of Galenic medicine or early modern schooling. This makes The Book in the Renaissance quite broadly accessible. It provides an excellent overview of how the modern world of books came into existence, something that may be of particular interest as that world faces new challenges and dramatic changes.