After the death of Denmark-Norway's foreign minister Andreas Peter Bernstorff in 1800, Crown Prince Frederick began exerting his will in all areas.

This was a high-risk strategy since many non-Danish ships were sailing under the Danish flag to gain their neutrality benefits, and though the policy proved profitable in its first year it also drew diplomatic protests from Great Britain.

When in 1800 it appeared that Russia would head a new League of Armed Neutrality Great Britain reacted, in summer that year having a squadron of 130 guns try to inspect a Danish convoy escorted by the 40-gun frigate Freya at Ostend.

So the Danish defense plan was that the ships available should protect the entrance to Copenhagen by lying anchored in the curved line from Trekroner Fort to Amager.

Crown Prince Frederick had, out of fear that the Swedes would be exempted from the Sound Dues, refused offers of help from them for the upcoming battle.

In the following days the British prepared to attack, and they sailed further south, past Copenhagen, to avoid the Danish land batteries at Sixtus, Quintus and Trekroner.

[2] Lord Horatio Nelson had been given command of twelve of the British ships of the line, and had the task of getting them through the tight defense that surrounded Copenhagen's reef, which was already extremely difficult to navigate through.

Because of this, Nelson sent a curiae with a letter to Crown Prince Frederick in which he argued that he could not account for the remaining crew on board Danish ships if they continued the fight after they had surrendered.

Crown Prince Frederick could from his position at the port see that the battle no longer had any purpose and agreed to a truce without consulting the Danish-Norwegian commanders, Olfert Fischer and Steen Bille.

Denmark-Norway, who had been forced to accept several bitter diplomatic defeats due to their neutrality policy, now turned to Britain through direct negotiations with Lord Hawkesbury.

Christian Bernstorff had in late May traveled to London in order to negotiate the return of the parts of the Danish-Norwegian fleet that had been captured by the British during the Battle of Copenhagen.

Denmark was now forced to react and Crown Prince Frederick stationed the majority of his army in Holstein, both as a proof that he did not want to participate in the hostilities in northern Germany and as protection in case of a French invasion.

But it would gradually get worse for Denmark-Norway to maintain its neutrality, and especially after Napoleon's final defeat of Prussia in the autumn of 1806, when the French emperor on 21 November that year declared the founding of the Continental System against the United Kingdom.

[8] Since Denmark-Norway refused to accept the British ultimatum, Britain chose to land a major force in Zealand at Vedbæk on 16 August 1807 without any formal declaration of war, and since King Christian VII and Crown Prince Frederick were in Holstein with the majority of the Danish army, the newly appointed commander Ernst Peymann had to face the British landing force with an inferior number of untrained militia.

After the bombardment on 6 September Peymann gave up and surrendered the city unconditionally to the British, this decision resulted in that he was sentenced to death, but later pardoned.

An offer of a British-Danish alliance was also given to Crown Prince Frederick after the attack on Copenhagen, but this was rejected, as France had already set an ultimatum to either join the Continental System, or prepare for war.

As a result of this declaration of war, Napoleon had chosen to send an auxiliary corps, consisting of troops from France, Spain and the Netherlands, to Denmark.

But Bernadotte's troops never got further than Zealand since the ice began to break up in the straits between Kattegat and the Baltic Sea as early as in mid-March, and the appearance of the British fleet made it difficult to cross over to Sweden.