Defenestration of Prague on May 23, 1618 (1646) This image depicts the events of May 23, 1618, the date on which a group of about 200 representatives of the Protestant Bohemian estates protested against restrictions on their religious freedom by storming the Bohemian Chancellery at Prague Castle and throwing two regents and their secretary out the window. A similar incident had occurred in Bohemia in 1419, at the beginning of the Hussite Wars. One crucial difference, however, was that in 1618 all three victims survived and were able to escape. The defenestration marked the beginning of the Bohemian Protestant revolt against the Catholic Habsburg monarchy. Today it is also considered the catalyst of the Thirty Years War. Colored copperplate engraving by Matthäus Merian the Elder (1593-1650), from Matthäus Merian, Theatrum Europaeum. Frankfurt am Main, 1646.