Shortly after, the duke of Burgundy sent letters to the king of France, to inform him of the route he had taken from Flanders to Burgundy, at what places he had paid his expenses, and where not, with his reasons for not paying. At the same time, he made him acquainted with the destruction of the castle of Tonnerre, and that he had destroyed it, because the count, his vassal, had frequently rebelled against him, had defied him, and had made enterprises on his territories, whence he had carried away much booty. This he had explained, lest it might be thought he was breaking the peace lately made before Arras, which he was firmly resolved to keep. The duke had besieged also Château-Belin, in the county of Burgundy, which likewise belonged to the count de Tonnerre; and although it was very strong, it was won by the great length of the siege. This castle he gave to his son, the count de Charolois, who during the lifetime of his father, styled himself count de Charolois and lord of Château-Belin. A council was now held at Constance, by many cardinals, patriarchs, bishops, archbishops, prelates and ambassadors from different kings and princes. There was a great schism in the church from the refusal of Pietro della Luna, entitled Pope Benedict to resign this dignity, although, for many reasons, the greater part of Christendom had withdrawn itself from his obedience. He had no power but in Spain and Arragon, in which last kingdom he resided, in a strong town on the sea-shore. In this year, the emperor of Germany caused the cardinal of Bologna, called pope John, to be arrested, and confined in prison in the duchy of Bavaria, for various crimes alledged against him. To restore peace to the church, the emperor had caused this council to be holden in Constance: it continued for the space of two years, before any persons came to attend it from Spain or Arragon. In the month of August, in the year 1416, a noble company of prelates and knights being assembled, the election of a true pope was proceeded upon. In the year 1417, the choice fell on the cardinal de Colonna, a Roman, who assumed the name of Pope Martin. CHAP. XV. COUNT WALERAN DE ST POL MARCHES ABOUT SIX HUNDRED COMBATANTS INTO THE DUCHY OF LUXEMBOURG.--THE DUKE OF ACQUITAINE GOES TO MEHUN-SUR-YEVRE. At this period, Waleran count de St Pol, still calling himself constable of France, left his county of St Pol with about six hundred combatants, men at arms and archers, of whom sixty at least were English. He marched them from his town of Bohain to that of Laon, but the gates were closed against him. He was much displeased thereat, and fixed his quarters below it. He thence marched by Rheims and Châlons to his town of Ligny in Barrois, whither his countess, sister to the duke de Bar, speedily followed him; and they there solemnised the feast of All-Saints.