Following the formation of the League of Cambrai in December 1508, events moved swiftly. Venice launched several desperate diplomatic initiatives to placate and appeal to old animosities among the various members of the League that had united against her, but her efforts were met with disdain.

The first incursion into Venetian territory came from the French in the area east of Milan. Venetian hopes rested in her mercenary army led by two experienced mercenary generals: Nicolo Count of Pitigliano and his younger cousin Bartolomeo d'Alviano.

On May 14, 1509, Alviano's force encountered and was set upon by French forces at Agnadello, southwest of Bergamo. Alviano's troops held a strong position and successfully repulsed attacks first by cavalry and then by pikemen. Alviano called upon Pitigliano, whose army was only a few miles away, to bring his forces up in support, but Pitigliano -- a more cautious commander -- apparently decided it was better to preserve his troops and he made no response. Perhaps a different reaction from Pitigliano would have changed the course of events.

In fact, however, the French king arrived with his own reinforcements instead, throwing Alviano's army into confusion, collapse and -- where possible -- flight. Venetian soldiers who were not killed or captured disappeared into the countryside. Nor had Pitigliano, by staying out of the battle, preserved his army. Instead, he found large segments of his own mercenary forces bolting en masse.

Suddenly, with the collapse of the Venetian army the pathway to the shores of the Venetian lagoon seemed to open wide to the forces of the League. Soon Venice saw her mainland cities falling to the enemy almost without resistance. Unless she could produce military and diplomatic miracles, she could anticipate an immediate siege of the lagoon city itself.