King Christian 8. Friedrich Carl Gröger · 1813 Frederiksborg Castle, Hillerød, Denmark

Since Frederik 6. left no male heirs, Christian Frederik was – as the son of the heir presumptive and in accordance with Danish succession law – the closest heir to the throne

In 1806, Christian Frederik married his cousin Charlotte Frederikke, but their marriage was never a happy one. Charlotte Frederikke gave birth to a son in 1808, who later became Frederik 7. The following year Prince Christian Frederik learned that the Princess was having an affair with her voice teacher (music teacher), the composer Edouard du Puy. The marriage was dissolved, and Charlotte Frederikke was banished to Horsens (in Jutland) and forbidden from ever seeing her son again.

Denmark had in 1807 entered the Napoleonic Wars on the side of France. In 1812, Russia and Sweden joined in an alliance in the fight against France. As a condition for their participation in the war against the French, the Swedes demanded that Norway be given to them after the war was over. England joined the anti-French alliance, and Napoleon's catastrophic defeat at Moscow during the winter of 1812 became the beginning of the end of the Napoleonic Wars. Sweden stood firm in her demand that Denmark cede Norway, and under these serious circumstances, Frederik 6. sent Crown Prince Christian Frederik to Norway the following year and appointed him governor.

Prince Christian Frederik joined the Norwegian independence movement and on May 17, 1814 signed the Eidsvoll Constitution, thereby giving Norway a free constitution. Christian Frederik was then named King of Norway, but had to abdicate on November 4 the same year under the threat of war when Sweden put into effect the Swedish-Norwegian Union they had been granted under the terms of the Peace Treaty in Kiel on January 14 that same year.

Queen Charlotte Frederikke Friedrich Carl Gröger · 1805 Rosenborg Castle, Copenhagen, Denmark

Frederik 6. had long had a somewhat chilly relationship with Christian Frederik and a hesitant attitude towards his liberal sympathies, but in the long run he was unable to prevent the Crown Prince from gaining political influence.

In 1831 Christian Frederik became a member of the State Council, though he did not exert his influence to any significant degree. As heir apparent and member of the Council, he showed great sympathy for the National Liberals and the Danish nationalism that was awakening in the Duchies of Southern Jutland. One of the most important questions he had to deal with was the new, advisory Assembly of the Estates of the Realm which Frederik 6. wanted to introduce, and the Prince realized that this was the first step towards a free constitution.

After the death of Frederik 6. in 1839, the 53 year-old Prince Christian Frederik inherited the throne. As Christian 8., he was able to place the crown on his own head at the last coronation in the history of Denmark. Danish liberals still remembered the King's efforts towards a democratic constitution in Norway 25 years earlier, but after acceding to the throne, Christian 8. still wanted to preserve the United Monarchy Constitution. The King saw a democratic constitution as a distant possibility which for the time being was not politically practical, and thus disappointed the liberals' expectations. The liberal opposition against the absolute monarchy grew the following year, and the peasants joined together and in 1846 established The Society of Friends of the Peasants, a society sympathetic to the political claims of the peasants.

On January 20, 1848 Christian 8. died of a case of blood poisoning he had contracted as a result of a bloodletting which his personal physician had prescribed. He was buried in Roskilde Cathedral and was succeeded by his son, Frederik 7.