During the summer, Charles remained at La Rivière exerting every effort to levy an army. It was no easy task, and the review held on July 27th showed a meagre return for his exertions. But he did not slacken his efforts. Lists were immediately drawn up showing the vacancies in each company, and his money stress did not prevent his offering increased pay as an extra inducement to recruits. "An excellent means of encouragement," comments Panigarola.

The necessity for his preparations was evident. An opportune legacy inherited by René of Lorraine enabled that dispossessed prince to work to better advantage than he had been able to do since Charles had convened the Estates of Lorraine at Nancy. Moreover, on the very day of the review of the deficient Burgundian troops, a Swiss diet at Fribourg adopted resolutions regarding, a closer alliance with René.[11] Louis XI. ostensibly maintained his truce with Charles but he had intimated that a French army would wait in Dauphiné ready "to help adjust the affairs of Savoy," and, at about the same time when Yolande was at court, he gave a gracious reception to a Swiss embassy, so that René did not feel himself without support as he advanced to recover his city.

The mercenaries left by Charles at Nancy were weak and indifferent—a brief siege, and the capital of Lorraine capitulated to Duke René. Charles was too late to prevent this mortifying loss. His forces, too, were a mere shadow. Three to four thousand men rallied round him in the Franche-Comté, a few hundred joined him in Burgundy, and as he skirted the frontier of Champagne he received slight reinforcements from Luxemburg. Then came Campobasso and his mercenary troops, and the Count of Chimay with such Flemish fiefs as had, individually, respected the duke's appeal. In all, the forces at Charles's disposition amounted to about ten thousand, far fewer than those at Neuss or at Granson.

At a diet of October 17th, the compact between René and the Swiss was confirmed, and the former was assured of efficient aid to help him repulse Charles in his advance into Lorraine. There was need. The city of Toul refused admission to both dukes, but furnished provision for Charles's troops, so that for the moment he was the better off of the two. René then proceeded to provision Nancy and to prepare it for a siege, while he himself proceeded to Pont-à-Mousson, and for several days the two adversaries were only separated by the Moselle. Charles's army was augmented daily by slight accessions from Flanders, and England, and by fragments of the garrisons of the towns in Lorraine that had yielded to René and the latter fell back, little by little. Charles in his turn held Pont-à-Mousson, and proceeded along the road to Nancy, not deterred by the Lorrainers.

It was on October 22nd, that Charles of Burgundy laid siege for the second time to Nancy. In thus entering into active hostilities, he was ignoring the advice of his councillors who were unanimous in begging him to devote the winter months to refitting his army in Luxemburg or Flanders. His position was really very dangerous. He had no base on which to rest as he had recovered no towns except Pont-à-Mousson. But he ignored the patent obstacles and tried assault after assault upon Nancy—all most valiantly repulsed. Within the walls, there was an amazing display of courage, energy, and good humour. As a matter of fact, the duke's reputation had waned, while the fear of his cruelty emboldened the burghers to hold out to the last ditch. Any fate would be better than falling into his hands, was the general opinion.

Throughout Lorraine, the captains of the garrisons seized every occasion to harry the Burgundians. Familiar with the lay of the land, with every cross-road and by-path, they were able to lie in wait for the foragers and to do much damage. Four hundred cavaliers, coming up from Burgundy, were attacked by one Malhortie de Rozière, and literally cut to pieces, while their horses changed sides with ease. Only a few escaped to report the fate of the others to Charles. Not long after, Malhortie, encouraged by this success, crept up to the Burgundian camp, fell upon the sleepers, and captured a goodly number of horses.

The troops on which Charles counted most confidently were Campobasso's. Several attempts were made to warn him that treachery was possible in that quarter if the commander were too much exasperated by delays in payment, too much tried by the ill-temper of his employer. But the duke persisted in being oblivious to what was passing under his eyes. Thus, while awaiting the moment for his final defection, the Italian found it possible to enter into communication with René and to retard the operations of the siege so as to give time for the advance of the army of relief.

The weather of this year was a marked contrast to the mild season of 1473. The winter set in early and the cold became very severe, almost at once. Their sufferings made the burghers very impatient for the relief of whose coming they could get no certain assurance. The Burgundian lines were held so rigidly that the interchange of messages between the city and her friends was rendered very difficult.[12] One Suffren de Baschi tried to slip through to Nancy, to tell the besieged that René was levying troops in Switzerland and would soon be with them. Baschi fell into the duke's hands and was immediately hanged. One story says that Campobasso was among the interceders for his life and received a box on the ear for his pains, an insult that proved the last straw in his allegiance to Charles. Commines, however, declares that the Italian urged the death of the captive, fearful of the premature betrayal of his own intended treachery.

This execution was one of those arbitrary acts condemned by public opinion as contrary to the code of warfare. Intense indignation among the Lorrainers and the Swiss forced René to retaliatory measures, and he ordered the execution of all the Burgundian prisoners. One hundred and twenty bodies hung on the gibbets, each bearing an inscription to the effect that their death was the work of le téméraire. The rancour of the proceedings became terrible. No quarter was given in any engagements. Slaughter was the only thought on either side.

Towards the end of December, one Thierry, a draper of Mirecourt, proved more successful than Baschi in reaching Nancy. His information, that René's army would leave Basel on December 26th, put heart into the beseiged and the bells rang out joyfully.