Northern-central Italy in the fourteenth and fifteenth centuries is divided into a number of warring city-states, the rest of the peninsula being occupied by the larger Papal States and the Kingdom of Sicily, referred to here as Naples.

Though many of these city-states are often formally subordinate to foreign rulers, as in the case of the Duchy of Milan, which is officially a constituent state of the mainly Germanic Holy Roman Empire, the city-states generally manage to maintain de facto independence from the foreign sovereigns that had seized Italian lands following the collapse of the Western Roman Empire.

The strongest among these city-states gradually absorbs the surrounding territories, giving birth to the Signorie, regional states often led by merchant families that found local dynasties.

War between the city-states is endemic, and primarily fought by armies of mercenaries known as condottieri, bands of soldiers drawn from around Europe, especially Germany and Switzerland, led largely by Italian captains.

Decades of fighting eventually see Florence, Milan and Venice emerge as the dominant players who agree to the Peace of Lodi in 1454, which sees relative calm brought to the region for the first time in centuries.

This peace will hold for the next forty years.