But the aim of Charles in these negotiations was simply to hold Lewis from any intervention in his campaign on the Rhine.

The siege of Neuss was not opened till the close of July, and its difficulties soon unfolded themselves.

Once master of the whole Rhineland, the house of Austria saw that Charles would be strong enough to wrest from it the succession to the Empire; and while Sigismund paid back his loan and roused Elsass to revolt the Emperor Frederick brought the whole force of Germany to the relief of the town.

From that moment the siege was a hopeless one, but Charles clung to it with stubborn pride through autumn, winter, and spring, and it was only at the close of June 1475 that the menace of new leagues against his dominions on the upper Rhineland forced him to withdraw.

So broken was his army that he could not, even if he would, have aided in carrying out the schemes of the preceding year.