continually spreading in Poland during the fifteenth century, prepared the ground; and the fact that nearly a half of the subjects of the Polish Crown, the Slavonic population of the South and East, professed the faith of the Greek Church, familiarised the Jagellon Kings with divergences in faith, and the people with the existence of other beliefs.
It was not long before the movement initiated by Luther spread to Poland, and it appeared first in Polish Prussia, the western part of the territory of the Teutonic Order, ceded by it in 1466 to King Casimir III. Danzig was the first centre of an active propaganda, and the urban population favoured the new opinions. The ecclesiastical authorities endeavoured to act with firmness, but found their authority insufficient. In 1525 the Reformers captured the town government, and the Reformation was set on foot. But in the following year Sigismund I, then King of Poland and Grand Duke of Lithuania, took forcible measures to suppress the Reform. In this, almost the only energetic step taken by that King against the spread of Reform, he was actuated by political motives. In 1523 Albert of Brandenburg, the last Grand Master of the Teutonic Order, had adopted the Reform, and in 1525 he converted the dominions entrusted to his charge into a hereditary dukedom; and Sigismund feared that the Reforming tendencies of West Prussia might lead the inhabitants into closer political relations with the emancipated master of East Prussia. In spite, however, of Sigismund's temporary success at Danzig, Lutheran opinions continued to spread, and finally triumphed in Polish Prussia.
In Poland itself frequent acts against the new opinions were passed by ecclesiastical synods, in 1527, 1530, 1532, 1542, and 1544. But the Church was powerless in face of the famous Polish privilege, "nemi-nem captivare nisi jure victum? and the other immunities of the nobles. The ecclesiastical Courts were regarded with general contempt. The hostility of the Diets was undisguised. In 1538 they forbade the Polish clergy to receive any preferment from the Pope, in 1543 they abolished annates, and in 1544 they subjected the clergy to ordinary taxation. Sigismund I issued an order in 1534 forbidding Polish students to study at foreign universities, but this order was cancelled in 1543; and the inaction of Sigismund proclaims either his impotence or his lack of zeal. His son, Sigismund II Augustus, who succeeded in 1548, was probably rather friendly than indifferent. In any case the power of the King was little; and individual nobles took what line they pleased without reference to King or Church.
In these circumstances not only did Lutheran views spread freely, but other heresies appeared. A society was formed at Cracow, under the influence of Francisco Lismanini, which not only ventilated the opinions of the more orthodox Reformers, but also cast doubt upon the doctrine of the Trinity. In 1548 the Reformation in Poland received a great impulse by the expulsion from Bohemia of the Bohemian Brethren,
