It had been settled that the congress was to hold its sessions in Ghent, although the citadel commanding that city was held by the Spaniards. The garrison was not very strong, and Mondragon, its commander, was absent in Zealand, but the wife of the veteran ably supplied his place, and stimulated the slender body of troops to hold out with heroism, under the orders of his lieutenant, Avilos Maldonado. The mutineers, after having accomplished their victory at Tisnacq, had been earnestly solicited to come to the relief of this citadel. They had refused and returned to Alost. Meantime, the siege was warmly pressed by the states. There being, however, a deficiency of troops, application for assistance was formally made to the Prince of Orange. Count Reulx, governor of Flanders; commissioned the Seigneur d'Haussy, brother of Count Bossu, who, to obtain the liberation of that long-imprisoned and distinguished nobleman, was about visiting the Prince in Zealand, to make a request for an auxiliary force. It was, however, stipulated that care should be taken lest any prejudice should be done to the Roman Catholic religion or the authority of the King. The Prince readily acceded to the request, and agreed to comply with the conditions under which only it could be accepted. He promised to send twenty-eight companies. In his letter announcing this arrangement, he gave notice that his troops would receive strict orders to do no injury to person or property, Catholic or Protestant, ecclesiastic or lay, and to offer no obstruction to the Roman religion or the royal dignity. He added, however, that it was not to be taken amiss, if his soldiers were permitted to exercise their own religious rites, and to sing their Protestant hymns within their own quarters. He moreover, as security for the expense and trouble, demanded the city of Sluys. The first detachment of troops, under command of Colonel Vander Tympel, was, however, hardly on its way, before an alarm was felt among the Catholic party at this practical alliance with the rebel Prince. An envoy, named Ottingen, was despatched to Zealand, bearing a letter from the estates of Hainault, Brabant, and Flanders, countermanding the request for troops, and remonstrating categorically upon the subject of religion and loyalty. Orange deemed such tergiversation paltry, but controlled his anger. He answered the letter in liberal terms, for he was determined that by no fault of his should the great cause be endangered. He reassured the estates as to the probable behaviour of his troops. Moreover, they had been already admitted into the city, while the correspondence was proceeding. The matter of the psalm-singing was finally arranged to the satisfaction of both parties, and it was agreed that Niewport, instead of Sluys, should be given to the Prince as security.