This chapter enlightens the papal martial power through three different questions. It first focuses on the military geography of the Pontifical States (Central Italy, Comtat Venaissin, Avignon). Strongholds were key in the affirmation of pontifical political authority. Their locations and features testify to the great care taken in their construction and management. The chapter then investigates the structure of the troops involved in both offensive and defensive enterprises. Cardinals acting as legates or vicars as well as papal officers were expected to exert strong control over companies led by potentially troublesome condottieri and local warlords. At sea, the popes relied mostly on private and foreign contractors. Finally, this chapter describes the socio-cultural composition of armies, intended as micro-societies defined by rules they adopted or developed themselves. Since they served the papacy just like lay principalities, they kept up with commonly shared knightly aspirations and military practices found across Europe.

The history of Italian warfare from 1300 to 1500 has been dominated by discussion of mercenary soldiers. Italian states used them throughout the Middle Ages and by the fourteenth century the practice evolved into a species of “system,” characterized by reliance on preformed bands of substantial size, containing also foreign soldiers from outside of the peninsula. The era of the “companies of adventure” (compagnie di ventura), as it is known, lasted from roughly the second decade to the end of the fourteenth century. It was followed by the emergence in the fifteenth century of individual native mercenary captains, condottieri, who settled into regular service with states and were the precursor to more permanent armies by the middle of the century. The reliance on mercenaries rendered Italian warfare out of touch with developments elsewhere in Europe, and left the peninsula unprepared for the onslaught of the armies of France and Spain and the Italian Wars in the sixteenth century. The invasion of Italy in 1494 by the French king Charles VIII was the signal event that revealed the weakness of Italian military institutions and more generally the strength of the rising nation state over its evolutionary predecessor, the city-state.