Schenkenberg castle was probably built in the early 13th century for the Habsburgs dynasty, both as a headquarters and to protect core areas around Brugg. The first written mention of the castle took place in 1243 when the Lords of Schenkenberg, a Habsburg vassel, were granted land around the castle. The ownership changed multiple times as the Habsburgs granted it to other vassels.
After the Habsburg defeat at the Battle of Sempach, they fell into financial difficulties and had to mortgage the castle. In 1415 the Habsburgs fell into disfavor with King Sigismund, after the Swiss Confederatesconquered the Aargau. The area on the left side of the Aare, including the Schenkenberger valley remained unchanged for the time being. However, in 1417, King Sigismund put the castle under his direct protection. The holder of the castle, Margaret of Fridlingen, sold the castle and the related rights in 1431 to Baron Thüring of Aarburg.
The bailiwick of Schenkenberg was at that time a fairly sovereign state. It extended over a large part of today's Brugg District. In 1451 Thüring ran into financial problems and sold the title and rights to his son-in-law Hans von Baldegg and Hans' brother Markwart. The Baldegger, who had fought on the side of the Habsburgs in 1386, allied themselves with Austria and pointedly drew the ire of the Confederates on himself. Increasingly, there were disputes with the citizens of the town of Brugg, who were subjects of Bern. In 1460 Bern finally had enough of the permanent provocations and occupied the castle driving out the Baldeggers.
The damage to the castle following the fight was immediately repaired. The castle became the seat of the Bernese bailiff and the center of the Herrschaft of Schenkenberg in the Bernese Aargau. The Baldeggers tried several times, by diplomatic and legal as well as in the Swabian War of 1499, to regain their castle and title. However they were always unsuccessful. Hans von Baldegg, the last of his line, died in 1510 of the plague.
Schenkenberg castle was in the northeastern corner of the territory of Bern, near the border with western Austria. Due to this strategic location Bern fortified the castle, but spent little in maintenance. In the early 18th Century, the castle became so dilapidated that the Governor and his family feared for their lives because the walls regularly crumbled. Finally the Council of the City of Bern gave up the castle, and the Governor moved in 1720 to the nearby Castle Wildenstein in Veltheim.
The castle fell into disrepair and was used as a quarry by the farmers of the area. In 1798 it became the property of the newly formed Canton of Aargau, the legal successor of the city of Bern. In 1837, the castle was purchased from a dubious, 'Herr von Schenkenberg', who, however, disappeared without a trace shortly thereafter. The castle was virtually abandoned for several decades. In a storm in 1917 east wall collapsed. The collapse spurred the authorities to declare the castle as unclaimed property, and put it up for auction in May 1918. For the symbolic sum of 50 francs it was sold to the Historical Preservation Society of Aargau. The building was repaired and extensive conservation was carried out.References:
First record of Kastelholma (or Kastelholm) castle is from the year 1388 in the contract of Queen Margaret I of Denmark, where a large portion of the inheritance of Bo Jonsson Grip was given to the queen. The heyday of the castle was in the 15th and 16th centuries when it was administrated by Danish and Swedish kings and stewards of the realms. Kastelhoma was expanded and enhanced several times.
In the end of 16th century castle was owned by the previous queen Catherine Jagellon (Stenbock), an enemy of the King of Sweden Eric XIV. King Eric conquered Kastelholma in 1599 and all defending officers were taken to Turku and executed. The castle was damaged under the siege and it took 30 years to renovate it.
In 1634 Åland was joined with the County of Åbo and Björneborg and Kastelholma lost its administrative status.