While political and economic issues determined the course of the Reformation in western and northern Europe, ethnic factors often proved decisive in eastern Europe, where people of diverse backgrounds had settled in the later Middle Ages. In Bohemia in the fifteenth century, a Czech majority was ruled by Germans. Most Czechs had adopted the ideas of Jan Hus, and the emperor had been forced to recognize a separate Hussite Church (see Chapter 11). Yet Lutheranism appealed to Germans in Bohemia in the 1520s and 1530s, and the nobility embraced Lutheranism in opposition to the Catholic Habsburgs. The forces of the Catholic Reformation promoted a Catholic spiritual revival in Bohemia, and some areas reconverted. This complicated situation would be one of the causes of the Thirty Years’ War in the early seventeenth century.

By 1500 Poland and the Grand Duchy of Lithuania were jointly governed by king, senate, and diet (parliament), but the two territories retained separate officials, judicial systems, armies, and forms of citizenship. The combined realms covered almost five hundred thousand square miles, making Poland-Lithuania the largest European polity, but a population of only about 7.5 million people was very thinly scattered over that land.

The population of Poland-Lithuania was also very diverse; Germans, Italians, Tartars, and Jews lived among Poles and Lithuanians. Such peoples had come as merchants, invited by medieval rulers because of their wealth or to make agricultural improvements. Each group spoke its native language, though all educated people spoke Latin. Luther’s ideas took root in Germanized towns but were opposed by King Sigismund I (r. 1506–1548) as well as by ordinary Poles, who held strong anti-German feeling. The Reformed tradition of John Calvin, with its stress on the power of church elders, appealed to the Polish nobility, however. The fact that Calvinism originated in France, not in Germany, also made it more attractive than Lutheranism. But doctrinal differences among Calvinists, Lutherans, and other groups prevented united opposition to Catholicism, and a Counter-Reformation gained momentum. By 1650, due largely to the efforts of the Jesuits (see New and Reformed Religious Orders), Poland was again staunchly Roman Catholic.

Hungary’s experience with the Reformation was even more complex. Lutheranism was spread by Hungarian students who had studied at Wittenberg, and sympathy for it developed at the royal court of King Louis II in Buda. But concern about “the German heresy” by the Catholic hierarchy and among the high nobles found expression in a decree of the Hungarian Diet in 1523 that “all Lutherans and those favoring them . . . should have their property confiscated and themselves punished with death as heretics.”7

Before such measures could be acted on, a military event on August 26, 1526, had profound consequences for both the Hungarian state and the Protestant Reformation there. On the plain of Mohács in southern Hungary, the Ottoman sultan Suleiman the Magnificent inflicted a crushing defeat on the Hungarians, killing King Louis II, many of the nobles, and more than sixteen thousand ordinary soldiers. The Hungarian kingdom was then divided into three parts: the Ottoman Turks absorbed the great plains, including the capital, Buda; the Habsburgs ruled the north and west; and Ottoman-supported Janos Zapolya held eastern Hungary and Transylvania.

The Turks were indifferent to the religious conflicts of Christians, whom they regarded as infidels. Christians of all types paid extra taxes to the sultan, but kept their faith. Many Magyar (Hungarian) nobles accepted Lutheranism; Lutheran schools and parishes headed by men educated at Wittenberg multiplied; and peasants welcomed the new faith. The majority of Hungarian people were Protestant until the late seventeenth century, when Hungarian nobles recognized Habsburg (Catholic) rule and Ottoman Turkish withdrawal in 1699 led to Catholic restoration.