On May 23, 1618, a group of Czech Protestant noblemen stormed into this Bohemian Chancellery room of the Old Royal Palace, threw two Vienna appointed Catholic governors plus their scribe out the window on the left, and elected their own king. This event is known as the Defenestration of Prague.
Their revolt for religious freedom was short-lived, as their Bohemian army was defeated by a superior Hapsburg Imperial force at the Battle of White Mountain (Bílá Hora) in 1620. This marked the beginning of the Thirty Years' War, which was fought throughout Europe. Bohemia was devastated by this war and the Jesuit led Counter-Reformation.
Incidentally, all three survived the Defenestration, not because angels kept their “feet from striking on stones”, but their 70-feet falls were cushioned by a large pile of manure.