Europe in Ferment 15profitable, was perfected during the 1440s. By 1500,
over 100 cities in Europe had at least one printing
press and as many as 20 million volumes had been
published. Books advanced new ideas and weakened
the hold of traditional ones. Within a few decades, the
treatises of Martin Luther and John Calvin initiated
the Protestant Reformation. Books also excited the
imagination and gave tangible expression to all man-
ner of dreams and longings. (Columbus’s restless
curiosity had been stimulated by books on geography
and navigation, especially Marco Polo’s account of his
journey to China.)
Incessant squabbles over land resulted in nearly
constant warfare. The military arts advanced accord-
ingly. Improvements in metallurgy made it possible to
cast bronze and iron cannon capable of containing
charges of gunpowder sufficient to hurl heavy balls
great distances. Mighty stone fortresses that had
stood for centuries were reduced to rubble by these
cannon in a few hours. By the early 1500s cannons
weighing a ton or more were mounted in sailing ships
or upon carriages pulled by teams of horses. Warfare
of this nature was expensive; the cost of constructing
fleets, equipping armies, and building massive fortifi-
cations required the collective resources of many
thousands. No longer an activity of rival cities or con-
tending noblemen, warfare demanded the resources
of entire nations.
A restless hunger for land, a population made
resistant to biological pathogens, an explosion in
communication and knowledge, a new technology
and organization of warfare, and the emergence of
powerful and contentious nation-states all imparted a
fateful dynamism to late fifteenth-century European
society. Plainly, these Europeans had not solved press-
ing social problems: Population growth exceeded
available food sources, poverty undermined political
stability, and war loomed larger and more ominous.
Equally plainly, the people of North America had
failed to solve basic social problems: Nomadic IndiansLike most world-changing inventions, the printing press of fifteenth-century Europe took advantage of technological innovations, chiefly
improvements in metallurgy (to cast letters and to carve the ridges of the pressing screw), and new concepts, such as increasingly standardized
rules for writing. By facilitating the spread of ideas, the printing press generated further technological advances.