The St Serf's Inch Priory was a community of Augustinian canons based, initially at least, on St Serf's Inch in Loch Leven. It was founded from St Andrews Cathedral Priory at the instigation of King David I of Scotland in 1150. There was a Scottish Céli Dé (or Culdee) establishment there in the first half of the 12th century, allegedly found by Bruide, son of Dargart, King of the Picts (696–706). Presumably it was dedicated to St Serb (Serf or Servanus), and there are indications that the Scottish establishment had a large collection of writings, mostly lost now or translated into Latin.
When the Augustinian priory was founded in 1150, the Scottish monks were absorbed into the established and those who refused to join were to be expelled. In the 15th century the priory begins to be referred to as 'Portmoak', perhaps indicating that the canons had partially relocated there from the island. Following more than four centuries of Augustinian monastic life and the resignation of the last prior, the Protestant king, James VI of Scotland, granted the priory to St Leonard's College, St Andrews. At some point in time, the structure was converted into a fishing hut or bothy.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.