Like his father he took service with Rudolf II who appointed him burgrave at Karlštejn. Under Rudolf's successor Matthias he became chamberlain of the Crown of Bohemia. Vilém supported the coronation of the devout Catholic Ferdinand of Inner Austria as Bohemian king against the resistance of the Protestant estates. In return Ferdinand vested him with the office of his representative at Prague, where he had to face the violent uprising of the nobles led by Jindřich Matyáš Thurn on 23 May 1618. Together with J. Bořita of Martinice he was thrown out of a window of the castle by an enraged Protestant multitude. He was subsequently arrested by the assailants after surviving the defenestration albeit with severe injuries.
Historické spisování ("Historical writings"), 1637–1651
This monumental (14 large-scale books) reminiscence in which Vilém comprehensively describes the causes and initiation of the Bohemian Revolt and the first phase of the Thirty Years' War, has importance for understanding of that era. His great annals are focused especially on the events of the years 1608–1619 on the territory of the Czech lands.