How a series of brutal Italian conflicts birthed the modern balance of power
Between 1423 and 1454, the Republic of Venice and the Duchy of Milan fought four intense campaigns for control of Northern Italy. This struggle reshaped the peninsula, marginalizing once-great cultural centers and establishing the five major powers that would define Italian politics for the rest of the century.
The Wars in Lombardy were driven by the territorial ambitions of Filippo Maria Visconti, the Duke of Milan, and the shifting alliances of his neighbors. What began as a local conflict over the regency of Forlì in 1423 quickly escalated into a regional struggle involving Florence, the Papal States, and eventually the Kingdom of Naples. These wars were characterized by the use of condottieri—mercenary captains like Francesco Sforza and Niccolò Piccinino—who often switched sides based on shifting political winds or financial incentives.
The conflict fundamentally altered the Italian map. As Venice expanded its territory to the banks of the Adda, the political structure of the region consolidated into five dominant powers: Venice, Milan, Florence, the Papal States, and Naples. Smaller, historically significant cities such as Siena, Pisa, and Mantua were pushed to the political periphery. The instability of this era was marked by dramatic reversals, such as the execution of the Venetian commander Carmagnola for suspected treason in 1432, and the eventual rise of Sforza, who transitioned from a mercenary leader to the Duke of Milan in 1450.
The fighting concluded with the Treaty of Lodi in 1454, which established a forty-year period of relative stability known as the Italic League. This agreement is frequently cited by historians as an early, conscious application of the balance of power principle in European diplomacy. By pledging mutual non-aggression, the five powers managed to maintain a fragile peace until 1494, when Milan’s decision to invite French intervention to press claims on Naples triggered the Italian Wars, ending the era of stability.
The legacy of these wars remains a subject of study for how they transformed a competitive collection of city-states into a structured, albeit tense, political system. While the period was marked by constant skirmishing and economic strain, the resulting diplomatic framework provided a template for managing regional hegemony that influenced European statecraft long after the final treaties were signed.
Source: Wars in Lombardy
