A contemporary woodcut of the defenestration in 1618.

Two incidents in the history of Bohemia, and a further one in the history of Czechoslovakia are known as the Defenestrations of Prague, the first in 1419 and the second in 1618 (though the second is generally considered The Defenestration of Prague). Both helped to trigger prolonged conflict within Bohemia and beyond. (A defenestration is an act of throwing someone out of a window.)

The First Defenestration of Prague involved the killing of seven members of the hostile city council by a crowd of radical Czech Hussites on July 30, 1419. The prolonged Hussite Wars broke out shortly afterward, lasting until 1436.

The Second Defenestration of Prague was an event central to the initiation of the Thirty Years' War in 1618. The Bohemian aristocracy was effectively in revolt following the election of Ferdinand, Duke of Styria and a Catholic zealot, to rule the Holy Roman Empire, which included Bohemia. In 1617, Roman Catholic officials ordered the construction of some Protestant chapels to cease, thus violating the right of freedom of religious expression as granted in the Majestätsbrief (Letter of Majesty) that had been issued by Emperor Rudolf II in 1609. At Prague Castle on May 23, 1618, an assembly of Protestants tried two Imperial governors (William Slavata and Jaroslav Martinic) for violating the Letter of Majesty, found them guilty and threw them, together with their scribe (Fabricius), out of the castle windows; they landed in some manure, and none was seriously injured.

An English translation of part of Slavata's report of the incident is printed in Henry Frederick Schwarz, *The Imperial Privy Council in the Seventeenth Century* (Cambridge, Mass.: Harvard University Press, 1943, issued as volume LIII of *Harvard Historical Studies*), pp. 344-347.