Sigismund III decided to help the Habsburgs and privately hired an infamous mercenary group called the Lisowczycy (name took from their founder Aleksander Józef Lisowski), who were unemployed after the end of the wars with Muscovy (Dymitriads) and were plundering and terrorizing the entire region of Lithuania. Sigismund sent the Lisowczycy to aid the Habsburgs towards the end of 1619. In the end, Ferdinand did not agree to any permanent concessions in Silesia, and only made Prince Karol Ferdynand (Władysław's brother) bishop of Wrocław. Neither did Habsburgs provide any help against the Ottoman Empire. The Lisowczycy crushed Transylvanian forces led by George I Rákóczi (Jerzy Rakoczy) at Závada, Humenné District and Humenné (November 13 or 21–24, sources vary; see Battle of Humenné) and started looting, plundering, killing "even children and dogs" (as a contemporary historian wrote), and burning Eastern Slovakia, thus forcing Bethlen to lift his siege of Vienna and try to save his own lands. Later, the Lisowczycy plagued Silesia and Bohemia and took part in the Battle of White Mountain.