Through the marriage of their daughter and heiress Juana with the son of the Emperor Maximilian, the Archduke Philip, the blood of Ferdinand and Isabel had merged in that of the House of Austria, and the aim of Ferdinand was nothing less than to give to the Austrian House the whole world of the west.

Charles of Austria, the issue of Philip's marriage, had been destined from his birth by both his grandfathers, Maximilian and Ferdinand, to succeed to the empire; Franche Comte and the state built up by the Burgundian Dukes in the Netherlands had already passed into his hands at the death of his father; the madness of his mother left him next heir of Castille; the death of Ferdinand would bring him Aragon and the dominion of the kings of Aragon in Southern Italy; that of Maximilian would add the Archduchy of Austria, with the dependencies in the south and its hopes of increase by the winning through marriage of the realms of Bohemia and Hungary.

A share in the Austrian Archduchy indeed belonged to Charles's brother, the Archduke Ferdinand; but a kingdom in Northern Italy would at once compensate Ferdinand for his abandonment of this heritage and extend the Austrian supremacy over the Peninsula, for Rome and Central Italy would be helpless in the grasp of the power which ruled at both Naples and Milan.

A war alone could drive France from the Milanese, but such a war might be waged by a league of European powers which would remain as a check upon France, should she attempt to hinder this vast union of states in the hand of Charles or to wrest from him the Imperial Crown.

Such a league, the Holy League as it was called from the accession to it of the Pope, Ferdinand was enabled to form at the close of 1511 by the kinship of the Emperor, the desire of Venice and Julius the Second to free Italy from the stranger, and the warlike temper of Henry the Eighth.
[Sidenote: The Holy League] Dreams of new Crecys and Agincourts roused the ardour of the young king; and the campaign of 1512 opened with his avowal of the old claims on his "heritage of France." But the subtle intriguer in whose hands he lay pushed steadily to his own great ends.