FERDINAND OF DENMARK

'Ferdinand of Denmark', Prince ''Frederik Ferdinand'' of the House of Oldenburg (November 22 1792 Copenhagen – June 29 1863 Copenhagen), was a Hereditary Prince of the Kingdom of Denmark until his death.
He was born as youngest child of Hereditary Prince Frederick of Denmark and Sophie Frederikke of Mecklenburg, thus being a grandson of late King Frederick V of Denmark and Norway.
Prince Ferdinand married (Frederiksborg August 1 1829) his first cousin once removed, Princess Caroline of Denmark (1793-1881), who was the eldest daughter of the sonless King Frederick VI of Denmark, who died 1839. Because of the Salic Law, Caroline did not then succeed to the Throne of Denmark, but it was inherited by the closest male relative, who happened to be Ferdinand's elder brother Prince Christian Frederick.
The number of male members of the Royal House was so low in those decades that Ferdinand himself was always very close to the succession. In 1848-63, the aged Ferdinand was the Heir Presumptive of Denmark.
Ferdinand died childless, which was one of the reasons why the main branch of the Danish Royal House soon went extinct, triggering the second war of Schleswig.