In the autumn of 1941, Petrozavodsk, the capital of Soviet Karelia, was occupied by Finnish army troops. The city, renamed by the invaders to Jaanislinna (“Fortress on Onego”), remained in the power of the new owners for a long two and a half years. The fundamental research of the Finnish historian J. Kulomaa, based on primary archival documents, is the only one to date that most fully illuminates the multifaceted history of Petrozavodsk during the occupation period. Published in Russian for the first time.