Ratiaria, originally conquered by the Dacians and later by the Romans, was known for its gold mine possibly exploited by Thracians. The Romans became involved around 75 BC, and by 29 BC, Ratiaria was a fortified city. Under Augustus, the Romans officially conquered the region, organizing it into the province of Moesia. Ratiaria became a key station with a legionary fortress and fleet. After the division of Moesia in 86 AD, it became the capital of Upper Moesia.
Legio IV Flavia Felix was stationed here until the conquest of Dacia (101-106 AD). Afterward, Ratiaria became a colonia named Colonia Ulpia Traiana Ratiaria (107 AD). In the 2nd and 3rd centuries, it prospered as a trade center. With the definitive abandonment of Dacia Traiana in 271, old castra were reopened. By 285, Ratiaria served as the capital of Dacia Ripensis, hosting the military governor and the Roman legion XIII Gemina. It later became an important Christian center in the 4th century, with recorded bishops and theologians. The city faced sackings by the Huns in 440-441 and the Avars in AD 586. Archaeological excavations started in 1958, revealing its historical significance.
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.