Before the French King took the final step, it had been necessary for him to surmount serious difficulties. The marriage of Charles with Anne of Britanny had involved France in hostilities with a league of powers. On the north, Henry VII descended and laid siege to Boulogne. England was bought off, by the treaty of Etaples (November, 1492), with an exorbitant money ransom, which caused Henry VII to forget that he had ever felt himself threatened by the presence of the French in Britanny. On the south France was menaced by the recently consolidated and extended kingdoms of Aragon and Castile. Their neutrality was purchased (January, 1493) by the retrocession without indemnity of the counties of Roussillon and Cerdagne, on the northward slope of the Eastern Pyrenees, pledged in 1462 to Louis XI by John of Aragon for 300,000 crowns. Maximilian, King of the Romans, had not only been robbed of his Breton marriage, but had also a claim under the treaty of Arras to the restitution of Franche Comte and Artois, with some minor places, part of the heritage of Charles the Bold. Under that treaty these provinces had been given to France as the dowry of Maximilian's daughter, whom Charles had now repudiated. In the war which followed this double wrong Maximilian had achieved partial, though for him unusual, success. His honour was satisfied, moreover he was now deserted by his allies. He could the more willingly accept the terms of the treaty of Senlis (May, 1493), which gave him in effect almost all there was left to give. The opportunity offered by this reconciliation Ludovico was not slow to seize. With the consent of France he gave to Maximilian the hand of his niece, Bianca Maria, with her more than princely dowry. In the following year Maximilian, who had in the interval succeeded to the empire, redeemed his obligation by bestowing on Ludovico the investiture of Milan, a little before the opportune death of Gian Galeazzo.
The heavy price that Charles was paying for a free hand in Italy must have shown Ludovico that the expedition was probable, and by the end of the year he knew for certain that it was imminent. He could no longer hope to withdraw from the alliance he had sought. On the other hand his own position was extremely dangerous. By the end of 1493 it was clear that Florence, Rome, and Naples were against him. Venice maintained a watchful neutrality. A rapid advance on Milan or Genoa, or both, might have overthrown his precarious rule. It was his task to amuse his enemies with fair words, delusive proposals, and treacherous promises until the time for action was past. Meanwhile the French King delayed. Warlike preparations had been in progress since 1492. In 1493 Charles assumed the title of King of Sicily and of Jerusalem. Additional taxes and forced loans were exacted to raise the necessary funds, royal domains were sold, and the revenues pledged in advance. At the beginning of 1494 the Neapolitan ambassadors were dismissed. On the 6th of March Charles entered Lyons to press on the mobilisation in person. In the same month the composition of the proposed force