Requesens, overwhelmed by difficulties, yet exerted himself to the utmost to put the best face on the affairs of government. His chief care was to appease the mutinous soldiery: he even caused his plate to be melted, and freely gave the produce toward the payment of their arrears. The patriots, well informed of this state of things, labored to turn it to their best advantage. They opened the campaign in the province of Guelders, where Louis of Nassau, with his younger brother Henry, and the prince Palatine, son of the elector Frederick III., appeared at the head of eleven thousand men; the Prince of Orange prepared to join him with an equal number; but Requesens promptly despatched Sanchez d'Avila to prevent this junction. The Spanish commander quickly passed the Meuse near Nimeguen; and on the 14th of April he forced Count Louis to a battle, on the great plain called Mookerheyde, close to the village of Mook. The royalists attacked with their usual valor; and, after two hours of hard fighting, the confederates were totally defeated. The three gallant princes were among the slain, and their bodies were never afterward discovered. It has been stated, on doubtful authority, that Louis of Nassau, after having lain some time among the heaps of dead, dragged himself to the side of the river Meuse, and while washing his wounds was inhumanly murdered by some straggling peasants, to whom he was unknown. The unfortunate fate of this enterprising prince was a severe blow to the patriot cause, and a cruel affliction to the Prince of Orange. He had now already lost three brothers in the war; and remained alone, to revenge their fate and sustain the cause for which they had perished. D'Avila soon found his victory to be as fruitless as it was brilliant. The ruffian troops, by whom it was gained, became immediately self-disbanded; threw off all authority; hastened to possess themselves of Antwerp; and threatened to proceed to the most horrible extremities if their pay was longer withheld. The citizens succeeded with difficulty in appeasing them, by the sacrifice of some money in part payment of their claims. Requesens took advantage of their temporary calm, and despatched them promptly to take part in the siege of Leyden.