"Historians have taken the 1618 Defenestration of Prague as marking the beginning of the Thirty Years’ War, a conflict that raged ferociously, mostly across Bohemia and other parts of the Holy Roman Empire, from 1618 to 1648, drawing in the armies of most of the European powers of the day. It was the most murderous war that Europe had known, and the Thirty Years’ War continued to hold that dubious honour until the even more deadly wars of the twentieth century."