The castle's story dates back to a fortress, Krogen (lit. "the Hook"), built in the 1420s by the Danish king, Eric of Pomerania. The king insisted on the payment of sound dues by all ships wishing to enter or leave the Baltic Sea passing through the Sound; to help enforce his demands, he built a powerful fortress at the narrowest point in the Sound. At the time, the Kingdom of Denmark extended across both sides of the Sound, and on the eastern shore the Helsingborg Castle had been in existence since the Middle Ages. With the two castles and guard ships it was possible to control all navigation through the Sound.
The castle was built on Ørekrog, a sandy tongue of land stretching into the sea from the coast of Zealand towards the coast of Scania. The castle consisted of a square curtain wall with a number of stone buildings inside. The stone building in the northeastern corner contained the king's residence. The building in the southwestern corner contained a large arched banquet hall. The building in the southeastern corner possibly served as the chapel. Large portions of the walls of Krogen are contained within the present-day Kronborg Castle.
King Christian III had the corners of the curtain wall supplemented with bastions in 1558-1559.
Frederick II's Kronborg
As a consequence of developments in the military technique of the era and the improved striking power of the artillery, it became clear that it was necessary to modernize the fortifications of Krogen. After the conclusion of the Northern Seven Years' War in 1570, King Frederick II initiated an extension of the advanced bastions to relieve the medieval curtain wall. The main architect was the Flemish architect Hans Hendrik van Paesschen and the fortification works were completed in 1577. After this, the castle acquired its current name of Kronborg (lit. "Crown Castle").
The castle itself was rebuilt from 1574 to 1585, with the separated buildings of Krogen being extended to three coherent wings. The north wing was equipped with chambers for the king, queen and her ladies-in-waiting as well as for the chancellery. In the south wing, the medieval building in the southeast corner was refitted as a modern chapel with the vaulted windows facing the chapel being retained. Frederick was a keen patron of theatre and players performed at the castle when he held court there in 1579.
Initially, the castle was reconstructed only to a height of two storeys. In 1578, however, the Flemish architect Anthonis van Obbergen was engaged as new master builder and work was undertaken to make Kronborg even larger and more magnificent. The sculptural work was coordinated by Gert van Groningen. As a sign of the new ambitions, the south wing was heightened by one storey and a new, gigantic ball room placed over the chapel. Soon after the west and north wings were also heightened by one storey. Finally, the east wing was also heightened with a passageway, The Queen's Gallery, allowing the Queen comfortable passage from her chambers in the north wing to the ball room in the south wing. The exterior walls were clad with sandstone from Scania, and the new castle was given a roof with copper sheeting.
Fire of 1629
In 1629, a moment's carelessness by two workmen caused much of the castle to go up in flames in the night between the 24 and 25 September. Only the Chapel was spared by the strength of its arches. King Christian IV put great efforts into restoring the castle. Already in 1631, the work was underway, led by the architect Hans van Steenwinckel the Younger. By 1639, the exterior — which in keeping with the king's wish was reconstructed without major changes — was once again magnificent, but the interior never fully regained its former glory. Furthermore, certain modernizations were made, and portals, chimneypieces, ceiling paintings and other decorations were renewed in Baroque style.
Swedish conquest of 1658
The siege of Kronborg in 1658
During the Dano-Swedish War of 1658–60, Kronborg was besieged, attacked and conquered by a Swedish army commanded by Carl Gustaf Wrangel. During the Swedish occupation, the queen of Sweden, Hedvig Eleonora of Holstein-Gottorp and the Swedish king's sister Maria Eufrosyne of Pfalz lived at Kronborg, where they were visited by Charles X of Sweden during the campaign and entertained the foreign ambassadors.
As a result of the Swedish occupation, Kronborg was deprived of many of its most precious art works, including the richly decorated fountain in the castle courtyard, Frederick II's canopy and a number of the large ceiling paintings commissioned by Christian IV for the ballroom.
Former military barracks on the outskirts of the castle in 2018
The Swedish conquest of Kronborg in 1658 demonstrated that the castle was far from impregnable. Afterwards, the defences were strengthened significantly. From 1688-90, an advanced line of defence was added called the Crownwork. Shortly afterwards, a new series of ramparts were built around it. After their completion, Kronborg was considered the strongest fortress in Europe.
From 1739 until the 1900s, Kronborg was used as a prison. The inmates were guarded by the soldiers billeted in the castle. The convicts had been sentenced to work on the castle's fortifications. The convicts were divided into two categories: those with minor sentences were categorised as "honest" and were allowed to work outside the castle walls; those serving sentences for violence, murder, arson or the like were categorised as "dishonest" and had to serve the full sentence doing hard physical labour inside the castle ramparts. Otherwise, they served their time under the same conditions: they all had to wear chains and spend nights in cold and damp dungeons. From January 17, 1772 to April 30, 1772, Kronborg was the place of imprisonment of Queen Caroline Mathilde (Princess Caroline Matilda of Great Britain), sister of George III, following the scandal of her affair with Johann Friedrich Struensee.
As Kronborg's importance as a royal castle diminished, the armed forces came to play a greater role. From 1785 to 1922, the castle was completely under military administration. During this period, a number of renovations were completed.
Sound Due and recent history
The captain of every ship sailing through the strait had to state the value of ship's cargo. Money that had to be paid to the King of Denmark was then calculated depending on the value of the cargo. The king had the right to buy the cargo for the price the ship's captain stated. This policy prevented captains from stating prices that were too low. The Royal Danish Army left the castle in 1923, and after a thorough renovation it was opened to the public in 1938.