In 1274, a moated defense tower was built on the site of today's Oberau castle. The specialty of this residential tower is the internal stairs and the external living rooms. In 1550, Ernst von Miltitz had an impressive, elongated new building built in the Renaissance style with accentuated gable tops next to the residential tower. In 1594 the building was thoroughly redesigned to create a renaissance castle.
In the 17th century painted wooden ceilings were installed in the castle, but their boards were used in a different way from 1807. The painting was retained. In 1803 the construction of Oberau Castle was restored. Valuable stucco work was created during this construction work. In the period from 1807 to 1878, the manor received its form that is characteristic of today. At the beginning of this period in particular, the castle got its striking appearance. Traditions from the end of 1853 tell of a single bridge - probably a drawbridge - that led across the moat to the castle. In 1860 the northeast wing was built, the style of which was adapted to the existing parts of the building. This gave the castle an angular floor plan and aneo-Gothic stair tower.
After the end of the Second World War, displaced persons were quartered in the castle. The entire building was occupied from the basement to the roof. After some families moved away, some rooms were rebuilt. In the period that followed, ten displaced families still found accommodation in the castle. These conversions were later also used by a children's home. As there was not enough space for the children's home, plans were made to demolish the castle. The demolition is delayed, however, as the resettlement families still lived in the castle. In 1946 the manor building was redesigned so that it could be used for other purposes. The large palace gardens were also significantly affected by the renovations.
References:Rosenborg Palace was built in the period 1606-34 as Christian IV’s summerhouse just outside the ramparts of Copenhagen. Christian IV was very fond of the palace and often stayed at the castle when he resided in Copenhagen, and it was here that he died in 1648. After his death, the palace passed to his son King Frederik III, who together with his queen, Sophie Amalie, carried out several types of modernisation.
The last king who used the place as a residence was Frederik IV, and around 1720, Rosenborg was abandoned in favor of Frederiksborg Palace.Through the 1700s, considerable art treasures were collected at Rosenborg Castle, among other things items from the estates of deceased royalty and from Christiansborg after the fire there in 1794.
Soon the idea of a museum arose, and that was realised in 1833, which is The Royal Danish Collection’s official year of establishment.