The various princes of the house of Austria, brothers, uncles, cousins, holding important posts all over the empire, were much alarmed in view of the peril to which the family ascending was exposed by the feebleness of Rhodolph. They held a private family conference, and decided that the interests of all required that there should be reconciliation between Matthias and Rhodolph; or that, in their divided state, they would fall victims to their numerous foes. The brothers agreed to an outward reconciliation; but there was not the slightest mitigation of the rancor which filled their hearts. Matthias, however, consented to acknowledge the superiority of his brother, the emperor, to honor him as the head of the family, and to hold his possessions as fiefs of Rhodolph intrusted to him by favor. Rhodolph, while hating Matthias, and watching for an opportunity to crush him, promised to regard him hereafter as a brother and a friend. And now Rhodolph developed unexpected energy, mingled with treachery and disgraceful duplicity. He secretly and treacherously invited the Archduke Leopold, who was also Bishop of Passau and Strasbourg, and one of the most bigoted of the warrior ecclesiastics of the papal church, to invade, with an army of sixteen thousand men, Rhodolph's own kingdom of Bohemia, under the plea that the wages of the soldiers had not been paid. It was his object, by thus introducing an army of Roman Catholics into his kingdom, and betraying into their hands several strong fortresses, then to place himself at their head, rally the Catholics of Bohemia around him, annul all the edicts of toleration, crush the Protestants, and then to march to the punishment of Matthias. The troops, in accordance with their treacherous plan, burst into Upper Austria, where the emperor had provided that there should be no force to oppose them. They spread themselves over the country, robbing the Protestants and destroying their property with the most wanton cruelty. Crossing the Danube they continued their march and entered Bohemia. Still Rhodolph kept quiet in his palace, sending no force to oppose, but on the contrary contriving that towns and fortresses, left defenseless, should fall easily into their hands. Bohemia was in a terrible state of agitation. Wherever the invading army appeared, it wreaked dire vengeance upon the Protestants. The leaders of the Protestants hurriedly ran together, and, suspicious of treachery, sent an earnest appeal to the king.