Deep within the vast Prague Castle complex is an easily overlooked feature that is quite literally a window to a devastating moment in history: the 1618 defenestration (the act of throwing someone out a window as a means of execution) that led to Europe’s Thirty Years’ War.

The origins of the war lie in an entanglement of complexities that are often simplified as a conflict between Protestants and Catholics. When the Habsburg Holy Roman Emperor Ferdinand II attempted to make Catholicism the sole religion of the empire, the Protestants of Bohemia (modern Czechia) protested the suppression of their religion. In anger, Bohemian nobles in Prague flung two representatives of Ferdinand out of a window of the Royal Palace.

The flingees survived their fall with only minor aches and pains, being cushioned by the flocculence of a manure pile, although Catholics claimed that a divine miracle saved them. Then, with significant chips on their shoulders, Ferdinand’s representatives reported their assault by the bunch of tossers, and the Thirty Years’ War began.

As unique as defenestration of one’s enemies may sound, this was actually the second historically significant window-tossing event in the city. The first Defenestration of Prague occurred in 1419 when an angry mob threw a judge out of the second story window of the New Town Hall, starting a rather shady tradition. Yet a third defenestration may also have occurred in 1948 when Communists were accused of assassinating Foreign Minister Jan Masaryk by similar means.

Although a reference to the Thirty Years’ War is unlikely to yield much reaction from most Americans, to central Europe it was a catastrophe of epic proportions, with consequences that reverberate through today. Fought between 1618 and 1648, estimates of fatalities range from 5 million to 11 million people, and it all began from a fit of jealousy in the Czech Office of the Old Royal Palace. If you happen to sashay into the Prague Castle and glaze over at its immensity, take time to visit the famous window for a moment of reflection.