So powerful were the Evangelicals that at the Diet of 1555 they held services in the face of the Catholic king, and passed a law abolishing the jurisdiction of the ecclesiastical courts. This measure, of course, allowed freedom of all new sects, both those then in control of the Diet and the as yet unfledged Antitrinitarians. Nevertheless a strong wish was expressed for a national, Protestant church, and had Sigismund had the advantages, as he had the matrimonial difficulties, of Henry VIII, he might have {143} established such a body. But he never quite dared to take the step, dreading the hostility of Catholic neighbors. Singularly enough the championship of the Catholic cause was undertaken by Greek-Catholic Muscovy, [Sidenote: 1562] whose Czar, Ivan, represented his war against Poland as a crusade against the new iconoclasts. Unable to act with power, Sigismund cultivated such means of combating Protestantism as were ready to his hand. His most trenchant weapon was the Order of Jesuits, who were invited to come in and establish schools. Moreover, the excellence of their colleges in foreign lands induced many of the nobility to send their sons to be educated under them, and thus were prepared the seeds of the Counter-Reformation. The death of Sigismund without an heir left Poland for a time masterless. During the interregnum the Diet passed the Compact of Warsaw by which absolute religious liberty was granted to all sects--"Dissidentes de Religione"--without exception. [Sidenote: January 28, 1573] But, liberal though the law was, it was vitiated in practice by the right retained by every master of punishing his serfs for religious as well as for secular causes. Thus it was that the lower classes were marched from Protestant pillar to Catholic post and back without again daring to rebel or to express any choice in the matter. The election of Henry of Valois, [Sidenote: Henry, May 11, 1573] a younger son of Catharine de' Medici, was made conditional on the acceptance of a number of articles, including the maintenance of religious liberty. The prince acceded, with some reservations, and was crowned on February 21, 1574. Four months later he heard of the death of his brother, Charles IX, making him king of France. Without daring to ask leave of absence, he absconded from Poland on June 18, thereby abandoning a throne which was promptly declared vacant.