In 1935, Himmler contacted a Finnish nobleman and author, Yrjö von Grönhagen, after seeing one of his articles about the Kalevala folklore in a Frankfurt newspaper. Grönhagen agreed to lead an expedition through the Karelia region of Finland to record pagan sorcerers and witches. Because there was uncertainty about whether the Karelians would allow photography, the Finnish illustrator Ola Forsell also accompanied the team.