After the defeat in 1864 there was a need for a new organization of both the army and the navy.
At the same time, the defense of the country had to be revised. Modern artillery could now reach very far, and was very accurate.
A fortress therefore had to be so far from the city that it could not be shelled. At the same time the fortifications had to be so large and powerful that it could not be attacked without very significant losses.
Both the foreign and defense policy were marked by national disasters at the time.
The bombing of Copenhagen and the loss of the navy in 1807, the state bankruptcy in 1813, the loss of Norway in 1815 and the war in 1864 with the subsequent loss of southern Jutland. By the ensuing peace in Prague, we lost the duchies and thus 2/5 of area and population.
Denmark had become a petty state with no significance.
Politicians and generals were already involved in many areas when drafting the new Army Act in 1867.
Should the country depend on the army, navy or both, and should they create a defense for the whole country, selected coastal areas at Zealand and Funen or just defend the capital.
Some argued that Copenhagen should be defended at all costs because it was the country’s center of culture, government, residence for the king and the entire center of power.
In 1906 Colonel Rolf Kall wrote:
“Indian chiefs and Negro kings can wage war as they roam from place to place. The civil machinery of civilized countries will soon cease if the enemy becomes lord of the heart of the country. Therefore, at least the capital, another important city or region, must be secured by fortifications. ”
Opponents believed that a fortress in Copenhagen would need all the troops available, leave the rest of the country open and, moreover, deprive the field army of its mobility. Finally, a fortress defense assumed that help came from outside, which Denmark had no agreements on.
This debate lasted, to a greater or lesser extent, almost all the way to the political defense agreement in 1909.
But at no point was the debate as fiery and polarized as in the years 1884 to 1894 while the fortress was erected.
There was much heated debate in the press, at lectures in defense associations where the officers certainly did not hold back in the eagerness for or against the fortifications.
The debate was largely about the threat to Denmark and the capital. In the years leading up to World War I, it became more and more evident that it was a great risk to challenge the great neighbor in the South.
In 1886 the constructions of the fortifications began. These works lasted to 1894, and for these eight years, no expenses at all were granted by the Parliament. A loophole in the constitution from 1849 was used.