|Hadmar and Siegfried von Mauer were brothers, who lived in 1147. They belonged to the family of Eisenbeutel. Siegfried named himself „of Albrechtsberg”. In 1149 his widow Friderun is mentioned. In Mauer Siegfried was a vassal of the count of Schalla. It seems he took Albrechtsberg as a fief from the lords of Perg, and it seems the newly erected castle was named after Albrecht of Perg. The lords of Perg were also stewards (sub-constables) of the nearby monastery of Melk and had vast properties in the area of Kilb. Until 1400 the history of Albrechtsberg in closely related to the Kilb-area. Between 1177 and 1190 Friedrich of Perg comitted a manslaughter.
||He was pardoned by the Duke, but lost all his possessions in Perg, Kilb and Albrechtsberg which were returned to him only as a fief. There are some indications however, that possession of Albrechtsberg did not pass to the Babenberger, but to the count of Plain and later to his successor the count of Schaunberg. No historical sources are known from the 13th century. In 1311 the Fleischessen, a dynasty from the surroundings of Kilb own the castle. In 1337 they founded the chapel of St. Achatius, but there is archeological proof that the chapel originates much earlier in romanic times. Only the early gotic additions mentioned above, could date back to 1337.