The 1800s
On 2 April 1801 a British fleet under the command of Admiral Sir Hyde Parker fought and defeated a Danish-Norwegian fleet anchored just off Copenhagen. Vice-Admiral Horatio Nelson led the main attack. He famously disobeyed Parker's order to withdraw, destroying many of the Dano-Norwegian ships before a truce was agreed. Copenhagen is often considered to be Nelson's hardest fought battle, surpassing even the heavy fighting at Trafalgar. It was during this battle that Lord Nelson famously "put the telescope to the blind eye" in order not to see Admiral Parker's signal to cease fire.
The Second Battle of Copenhagen (or the Bombardment of Copenhagen) (16 August – 5 September 1807) was a British preemptive attack on Copenhagen, targeting the civilian population in order to seize the Dano-Norwegian fleet. The British landed 30,000 man and surrounded Copenhagen. The attack continued for the next three days and resulted in the death of at least 2,000 civilians and destruction of most of the city. The devastation was so great because Copenhagen relied on an old defence-line rendered virtually useless by the increase in shooting range available to the British.
The political after-effects of the conflict did even greater damage to the city and the nation. If the previous 25 years had been a heyday for Copenhagen, the next 25 years became a period of poverty. Surprisingly science, literature and art blossomed. Following the July Revolution of 1830 the Danish liberal and national movement gained momentum, and after the European Revolutions of 1848 Denmark became a constitutional monarchy on June 5, 1849. On January 1, 1840, the city was given a new municipal constitution which was expanded on March 4, 1857.
Roughly at the same time the ramparts of the city opened to allow new housing to be built around the lakes ("Søerne") which bordered the old defence system to the west. This dramatic increase in space was long overdue, not only because the old ramparts were out of date as a defence system, but also because of bad sanitation in the old city. As the area within the ramparts had been almost constant since the reign of Christian IV despite a fourfold increase in the population, the buildings had become taller and the amount of space available to residents had decreased. By relaxing the demarcation line introduced as a result of the defences, unrestricted permission to build property outside the lakes was introduced in 1852. This caused a considerable growth in Nørrebro, Vesterbro and Frederiksberg. A new neighbourhood arose in 1861–77 on the island of Gammelholm as Holmen naval base was moved to Nyholm, and large parts of Nyboder were changed into ordinary residences. In 1868 it was decided to remove the ramparts and from 1872 the old glacises were converted into residential areas. By the construction of Frihavn harbour in 1894 another neighbourhood was founded stretching towards Hellerup. In 1900–01, the large developments of Brønshøj and Valby followed.
The Second War of Schleswig in 1864 (where Denmark lost a third of its area) was the primary reason the old ramparts were replaced by the Fortification of Copenhagen.
Read more about this topic: History Of Copenhagen