Brunegg is first mentioned in first half of the 12th Century as "Bruneco". In 1273 it was mentioned as "Brunegge". Brunegg castle was built on a hill at the edge of the Jura mountains in the 13th Century. This castle was probably built, together with Wildegg castle in nearby Wildegg, as part of the Habsburg border defenses. The castle was occupied by Habsburg knights, including Schenken von Brunegg and Gessler von Meienberg. In 1415 the castle was besieged by Bernese troops, but they lifted siege after a counterattack. However, Bern conquered the Aargau, and awarded the fief to the Segenser or Segesser family. Between 1538-1798, the castle was subordinate to the Governor of Lenzburg. In 1815 it became the property of the Hünerwadel family of Lenzburg. The current owners of the castle, the Salis family, inherited the castle through marriage from the Hünerwadels. For hundreds of years, the castle was poorly maintained, and in the 17th Century it was heavily damaged twice through storm and tempest. In 1805-06, the keep and out buildings were repaired and the roof was rebuilt.