Third Defenestration of Prague Sparks Thirty Years' War
Religious tensions in Bohemia had escalated after Emperor Rudolf II's Letter of Majesty granted limited Protestant freedoms in 1609. Catholic officials closed Protestant chapels in Broumov and Hrob, violating those guarantees. On May 23, 1618, Protestant nobles assembled at Prague Castle, tried imperial regents Jaroslav Martinic and William Slavata along with their secretary, and threw the three men from a window into a dung heap below. The victims survived the fall, but the act symbolized open Bohemian defiance of Habsburg Catholic authority. It prompted the formation of a Protestant directorate and a revolt against Emperor Ferdinand II.