Question: Heinrich Holk was a mercenary in the service of the military leader of what heritage?
Sentence (from "Albrecht von Wallenstein"): Albrecht Wenzel Eusebius von Wallenstein ( ; Czech: "Albrecht Václav Eusebius z Valdštejna" ; 24 September 158325 February 1634), also von Waldstein, was a Bohemian military leader and Holy Roman Empire Count palatine, who offered his services, an army of 30,000 to 100,000 men, during the Thirty Years' War (1618–48), to emperor Ferdinand II.
Relevant evidence: Yes