Heinrich Holk (1599–1633) was a Danish-German mercenary in both Christian IV of Denmark's and Albrecht von Wallenstein's service during the Thirty Years' War. Serving Christian IV, Holk was commander of the Danish-Scottish force in the Battle of Stralsund in 1628, defending the besieged town of Stralsund against Wallenstein's imperial army. When Christian was forced into a peace with Wallenstein in 1629, Holk entered the latter's service. In 1632, he was given a cavalry command. His unit, referred to as "Holk's Horse", was known for their fierce attitude not only in battle, but also in pillage and rape - "notorious even in an age of atrocities". He took part in the devastation and looting of the Electorate of Saxony, and faced Gustavus Adolphus of Sweden's cavalry in the Battle of Lützen.