To those to whom the point of view of the Renaissance does not promptly suggest itself from this plain statement of fact, all unargued as we leave it, we recommend a perusal of Gianpietro de Crescenzi's Il Nobile Romano.
The marriage of Lucrezia Borgia to Giovanni Sforza tightened the relations between the Pope and Milan, as the Pope intended.

Meanwhile, however, the crafty and mistrustful Lodovico, having no illusions as to the true values of his allies, and realizing them to be self-seekers like himself, with interests that were fundamentally different from his own, perceived that they were likely only to adhere to him for just so long as it suited their own ends.

He bethought him, therefore, of looking about him for other means by which to crush the power of Naples.
France was casting longing eyes upon Italy, and it seemed to Lodovico that in France was a ready catspaw.

Charles VIII, as the representative of the House of Anjou, had a certain meagre claim upon the throne of Naples; if he could be induced to ride south, lance on thigh, and press that claim there would be an end to the dominion of the House of Aragon, and so an end to Lodovico's fears of a Neapolitan interference with his own occupation of the throne of Milan.
To an ordinary schemer that should have been enough; but as a schemer Lodovico was wholly extraordinary.

His plans grew in the maturing, and took in side-issues, until he saw that Naples should be to Charles VIII as the cheese within the mouse-trap.