Duchy of Nysa
Charles was a staunch Catholic. Upon his appointment as Breslau prince-bishop, he strongly protested against the 1609 Letter of Majesty, issued by his cousin Emperor Rudolf II to treat all religions equally in the Bohemian crown land of Silesia, and failed to succeed as a Silesian "Landeshauptmann" governor. When after the outbreak of the Thirty Years' War in 1618 the Protestant Silesian estates rebelled and acknowledged Frederick V of the Palatinate as king, the prince-bishop fled to the Polish court of King Sigismund III Vasa and later moved to Brixen. After the 1620 Battle of White Mountain he returned to forcefully reintroduce Catholicism in his Duchy of Nysa. He founded a Jesuit college Carolinum(Nysa) there in 1622. After he had received the Bohemian County of Kladsko from Emperor Ferdinand II in 1621, he had the area likewise occupied by Imperial troops and forcefully reverted to Catholicism.