[2] Born into the House of Oldenburg, the royal house which had ruled Denmark since its foundation there in the 15th century, he was the second, but eldest surviving, child to the then Prince Christian Frederick of Denmark, the future King Christian VIII, and his first wife Duchess Charlotte Frederica of Mecklenburg-Schwerin.

The young prince was baptised on 17 October by the royal confessor Nicolai Edinger Balle, Bishop of Zealand, with the names Frederik Carl Christian.

Rasmussen was denounced as a vulgar gold digger by her enemies, but viewed as an unaffected daughter of the people by her admirers and seems to have had a stabilizing effect on him.

[citation needed] The expectation that Frederick would not likely produce offspring, despite numerous affairs, was widespread, but sources rarely state the reasons.

Maaloe possesses four letters from Frederick to Marie Poulsen acknowledging paternity; these are quoted in her book, published in 2009.

It has been claimed Frederick had a same-sex relationship with his friend, Carl Berling (1812–1871), publisher and owner of the newspaper Berlingske Tidende.

To retain a tinge of decency, the King married Louise Rasmussen and the trio then moved into the royal castle, where Berling was appointed Chamberlain and remained until 1861.

The public indignation within higher circles over Frederick's morganatic marriage is well-known, but reasons have rarely been explained in detail.

The Schleswig-Holsteiners wanted an independent state while the Danes wished to maintain South Jutland as a Danish area.

The king soon yielded to the Danish demands, and in March he accepted the end of absolutism, which resulted in the June Constitution of 1849.

In 1854, he contributed to the fall of the strongly conservative Ørsted cabinet, and in 1859–60, he accepted a liberal government appointed on the initiative of his wife.

In some of these affairs, he overstepped the mark beyond any doubt; on the other hand, the first Danish constitution was somewhat vague as regards to the limits of royal power.

This period was marked by some political and economic reforms, such as the beginning of the demolition of the walls around Copenhagen and, in 1857, the introduction of free trade.

But Frederick VII was the last of Frederick III's male line, therefore, his nearest kinsmen in the male-line, the Schleswig-Holstein ducal lines of Augustenborg and Glücksburg (cadet branches of Denmark's earlier, non-hereditary kings), were not entitled to succeed to Denmark's throne, although they retained hereditary claims to the duchies of Schleswig and Holstein.

The closest female relatives of Frederick VII were the issue of his paternal aunt, Princess Louise Charlotte of Denmark, who had married a cadet Hessian prince.

This made him a relatively attractive royal candidate from the Danish viewpoint since, as a descendant of Frederick III, he was eligible to succeed in Denmark, although not first in line.

Christian of Glücksburg also had married Princess Louise of Hesse-Kassel, second-eldest daughter of the closest female relative of Frederick VII's.