Duke of Friedland (1625), Duke of Mecklenburg (1629), Czech magnate and military entrepreneur. At the outbreak of the Thirty Years War he remained loyal to Emperor Ferdinand II and in 1621 was made governor of Bohemia, a position from which he profited enormously. He served as commander‐in‐chief of the emperor's Catholic forces (1625–30), but after driving the Danes from north Germany, he tried to establish his own empire on the Baltic, and the German princes prevailed upon the emperor to dismiss him. He was subsequently recalled as imperial general (1632–34) to deal with the ascendant Swedes and Saxons. Having become embittered by his earlier dismissal, he was determined to build up his personal power and his secret negotiations with the enemy were discovered. Ferdinand again removed him from command and shortly afterwards connived at his assassination.