Large parts of the Kamp Valley and the Horn Basin were already favoured settlement areas in prehistoric times.
In medieval times the Waldviertel was still part of the great Northern Forest that separated the three large settlement regions comprising the Bavarian-Austrian Danube Plain, the Weinviertel region and South Moravia from the Bohemian Basin. The Kamp River had an important position as a transport connection to the natural traffic artery, the Danube River.
About 1.000 years ago the settlement of this hardly accessible region began under the leadership of the Babenberg margraves. Several free noble dynasties initiated the colonisation and thereby established a number of counties. A distinct example in the area of the Horn Basin is the region of the mighty Counts of Poigen-Hohenburg-Wildberg. Around the year 1156, the medieval realm known as “Poigreich” was united with the march, which was elevated to the status of a duchy; the red-white-red escutcheon from the House of Babenberg was also adapted.
The Rosenburg was mentioned in a document for the first time in 1175, in relation to the area of the border along the Kamp River between Poigreich and the Babenberg settlements with the centres, the Benedictine Altenburg Abbey and the Gars-Thunau castle complex. A “Gozwin de Rosenberg” is mentioned as owner. The name is also a crucial factor in the naming.