History of germany

After Augsburg: 1555-1619

The Augsburg formula preserves for half a century an uneasy peace in the German lands, while princes use their religious freedom as a form of diplomacy. 

Catholic rulers can be sure of strong support from a newly invigorated Rome after the Council of  Trent; an energetic role is now played in their territories by the new order of Jesuits. Lutheran princes gain strength not only from each other but from Protestant kingdoms to the northwest, Denmark and Sweden. And the minority of Calvinist territories can expect friendship from France during the reign of  Henry IV. 
Early in the 17th century the two sides form up in opposing blocs, each headed by a branch of the Wittelsbach family. The Wittelsbachs of the Rhine Palatinate, in southwest Germany, are Calvinist; they lead the Protestant Union, formed in 1608. The Wittelsbachs of Bavaria, just to the east, form the Catholic League in the following year. 
This confrontation does not immediately lead to armed conflict - until the Protestants of distant Bohemia elect as their king, in 1619, the Calvinist Wittelsbach, Frederick V. The response by the Catholic League, in alliance with pope and emperor, becomes one of the opening encounters of the Thirty Years' War.

The Winter King: 1619-1620

In accepting the Bohemian throne, and being crowned in Prague in November 1619, Frederick V is perpetrating an extremely inflammatory act within the edgy community of the German states. Ferdinand II, Habsburg successor to the kingdom of Bohemia, has been elected Holy Roman emperor in August of that year.

Frederick owes Ferdinand allegiance, as one of the German princes and as an imperial elector (the elector palatine of the Rhine). Instead, by popular demand in Bohemia, he is usurping his lord's place. 
Ferdinand is able to organize a powerful army against the Protestant upstart. The bulk of it comes from the duchy of Bavaria, a Catholic line of the Wittelsbachdynasty and deeply hostile to the Protestant branch headed by Frederick in the Palatinate. In return for his support the Bavarian duke, Maximilian I, is promised Frederick's hereditary lands and his status as an imperial elector. 
Frederick, by contrast, receives messages of goodwill but little practical help from the Protestant states.The issue is decided in a single brief encounter. The Bavarian army, under its distinguished general Johann Tserclaes von Tilly, marches on Prague. A battle at the White Mountain, to the west of the city, lasts only an hour before the Protestant army gives way. On the evening of that same day, 8 November 1620, almost exactly a year after his coronation, Frederick flees from Prague with his family.
His wife is Elizabeth, daughter of James I of England. Their brief reign causes Frederick and Elizabeth to become known as the Winter King and Queen. (But unwittingly they found a dynasty. A century later their grandson becomes king of Great Britain asGeorge I).