This is the Finnish Historical Dance Wiki. Here you can find information on where historical dances are danced in Finland and numerous instructions for them (in Finnish).
Historical dances are dances which have been recorded in writing, but do not have a continuing dance tradition. Therefore they need to be reconstructed from the written documents and dance guides, which can often be quite ambiguous. In Finland many historical dance groups are not associated with the SCA (though several are), and are not especially exact in historicity. Many of the dances are modern creations that are similar to historical dances. Also other types of dances are often danced in the groups, such as folk dances and Bordonian dances.
Below are some of the topics covered in this wiki. They are in Finnish, but you can try to use Google translate for translations.