Bourbon was Constable of France, the highest of the French nobles both from his blood and the almost independent power he wielded in his own duchy and in Provence.

But a legal process by which Francis sought to recall his vast possessions to the domain of the crown threatened him with ruin; and driven to secret revolt, he pledged himself to rise against the king on the appearance of the allied armies in the heart of the realm.

His offer was eagerly accepted, and so confident were the conspirators of success that they at once settled the division of their spoil.

To Henry his hopes seemed at last near their realization; and while Burgundy fell naturally to Charles, his ally claimed what remained of France and the French crown.

The departure of Francis with his army for Italy was to be the signal for the execution of the scheme, a joint army of English and Imperialists advancing to Bourbon's aid from the north while a force of Spaniards and Germans marched to the same point from the south.