What is Kastelholm witch trials?

The Kastelholm witch trials, which took place in Kastelholm on Åland between 1665 and 1668, were the biggest witch trial in the history of Finland. It was also almost unique in its character for Finland, where witch trials were normally small, with a single and often male defendant accused of sorcery. In contrast, the Kastelholm witch trials were a mass trial where several women were accused of attending a witches' Sabbath and making a pact with the Devil in the manner of contemporary continental witchcraft demonology, and in both instances it was almost unique for Finland, where only the Österbotten witch trials of 1674-1678 were similar to it. It resulted in the execution of six women.