Discord between Hapsburgs and Czechs and between Catholics and the followers of the reformed creeds erupted again into an open clash in the early seventeenth century. At that time, the Czechs were able to take advantage of the struggle between two contenders to the imperial throne, and in 1609 they extracted a Letter of Majesty from Emperor Rudolf II (1576-1612) that promised toleration of the Czech Reformed Church, gave control of Charles University to the Czech estates, and made other concessions. Rudolf's successor, Matthias (1612-17), proved to be an ardent Catholic and quickly moved against the estates. Violation of promises contained in the Letter of Majesty regarding royal and church domains and Matthias's reliance on a council composed of ardent Catholics further increased tensions.

In 1618 two Catholic imperial councillors were thrown out of a window of a Prague castle, signaling an open revolt by the Bohemian estates against the Hapsburgs. The Bohemian estates decided to levy an army, decreed the expulsion of the Jesuits, and proclaimed the Bohemian throne to be elective. They elected a Calvinist, Frederick of the Palatinate, to the Bohemian throne. The Bohemian troops confronted the imperial forces. On November 8, 1620, the Czech estates were decisively defeated at the famous Battle of White Mountain.

Data as of August 1987