The Stableyard and Koldinghus date from the same period. They are both parts of the castle that was built on the border between Jutland and Schleswig, probably in the year 1268.
The main castle building was situated where Koldinghus stands today, while the Stableyard was located in a lower position, bordered to the east and south by a moat. The area toward the north, where the castle lake is now located, used to be a large area of swampy land, which provided effective protection against attacks from the north. Nothing is known about the buildings that stood on the bank between the moat and this swampy area.
It is certain, however, that from the middle of the sixteenth century, these buildings housed the royal stables. At that time, the stables were housed in half-timbered buildings, which were replaced during the seventeenth century by the brick buildings that are still standing today. During the reign of King Christian IV, solid tower-like pavilions stood in the two corners facing east. These were later removed, but remains of the thick tower walls can still be seen in the partitions between the offices.
After the Swedish Wars of 1657–60, the decision was made to fortify Koldinghus castle and stableyard, which were provided with a number of bastion-like installations. It is possible that these were never fully completed, but they were in any case demolished a few years later.
In 1717–18, King Frederik IV had the Stableyard equipped so that it could be used by the cavalry. King Christian V, before him, had already divided the royal estates into cavalry districts, whose task it was to supply horsemen in case of war. King Frederik IV expanded this system and improved its efficiency, so the stableyard served as the base for the Koldinghus cavalry district over the century that followed.
During the England Wars of 1808–14, the large buildings were used as storage space for military equipment and materials. The fire in the castle on the night between 29 and 30 March 1808 did not reach the Stableyard.
From 1819 to 1842, the stableyard served as quarters for two squadrons of the Holstein Regiment of Lancers, who kept their horses there. From 1845 to 1862, the stableyard served as a stud-farm for the army. Later, the Stableyard was put to a variety of uses, including serving as a schoolhouse for one of the town's many small private schools.
In 1907, the military once again assumed control of the Stableyard, which was outfitted as a remount depot, i.e. a place where young horses were raised and broken in for use by the army, a practice that continued until 1923. No horses have been kept in the stableyard since then, but the iron rings to which the horses were tethered can still be seen in the old stalls, and the paved floors are still preserved in a few areas.
After the horses were removed, the military used the stableyard as a depot, and beginning in 1926, the offices of the Danish Defence Construction Service were located there. During the last two years of World War II, however, the Gestapo took over the building, where they set up headquarters for southern Jutland and North Schleswig. One of the prison cells, Zelle II, has been preserved intact, and signatures and inscriptions left by prisoners can still be read on its walls. The cell is a protected historical site and forms a part of Museet på Koldinghus. After the war, the stableyard served as a supply base for the Danish Brigade in Schleswig-Holstein.
Today the Stableyard houses offices and training facilities for the Home Guard, offices for the City Archive and workshop and depos for the museum.