Frederick IV (October 11, 1671 - October 12, 1730) king of Denmark and Norway from 1699. Son of Christian V, cousin to Charles XII of Sweden and Ulrike Eleonora of Sweden. He married Louise of Mecklenburg-Güstrow on December 5, 1695 and by her became father of five children, including Christian VI. Following her death on March 15, 1721, he married his mistress Anna Sophie Reventlow (on April 4, 1721). Three children were born of this marriage. Frederick IV commanded the Danish troops at the battle of Gadebusch 1712.