The magistracy did not dare to accept so bold a proposition; the general council, composing the more popular branch of the municipal government, were comparatively inclined to favor Nassau, and many of its members voted for the downfall of the tyrant. Nevertheless the demands of Count Louis were rejected. His position thus became critical. The civic authorities refused to, pay for his troops, who were, moreover, too few, in number to resist the inevitable siege. The patriotism of the citizens was not to be repressed, however, by the authority, of the magistrates; many rich proprietors of the great cloth and silk manufactories, for which Mons was famous, raised, and armed companies at their own expense; many volunteer troops were also speedily organized and drilled, and the fortifications were put in order. No attempt was made to force the reformed religion upon the inhabitants, and even Catholics who were discovered in secret correspondence with the enemy were treated with such extreme gentleness by Nassau as to bring upon him severe reproaches from many of his own party.
A large collection of ecclesiastical plate, jewellery, money, and other valuables, which had been sent to the city for safe keeping from the churches and convents of the provinces, was seized, and thus, with little bloodshed and no violence; was the important city secured for the insurgents. Three days afterwards, two thousand infantry, chiefly French, arrived in the place. In the early part of the following month Louis was still further strengthened by the arrival of thirteen hundred foot and twelve hundred horsemen, under command of Count Montgomery, the celebrated officer, whose spear at the tournament had proved fatal to Henry the Second. Thus the Duke of Alva suddenly found himself exposed to a tempest of revolution. One thunderbolt after another seemed descending around him in breathless succession. Brill and Flushing had been already lost; Middelburg was so closely invested that its fall seemed imminent, and with it would go the whole island of Walcheren, the key to all the Netherlands. In one morning he had heard of the revolt of Enkbuizen and of the whole Waterland; two hours later came the news of the Valenciennes rebellion, and next day the astonishing capture of Mons. One disaster followed hard upon another. He could have sworn that the detested Louis of Nassau, who had dealt this last and most fatal stroke, was at that moment in Paris, safely watched by government emissaries; and now he had, as it were, suddenly started out of the earth, to deprive him of this important city, and to lay bare the whole frontier to the treacherous attacks of faithless France. He refused to believe the intelligence when it was first announced to him, and swore that he had certain information that Count Louis had been seen playing in the tennis-court at Paris, within so short a period as to make his presence in Hainault at that moment impossible. Forced, at last, to admit the truth of the disastrous news, he dashed his hat upon the ground in a fury, uttering imprecations upon the Queen Dowager of France, to whose perfidious intrigues he ascribed the success of the enterprise, and pledging himself to send her Spanish thistles, enough in return for the Florentine lilies which she had thus bestowed upon him.