District zoning of new territories of Karelian-Finnish Union Republic and Leningrad region in 1940

The article deals with the issue of administrative zoning conducted on the former Finnish territories - the Karelian Isthmus and the Northern Ladoga area, which were annexed by the Soviet Union after the end of the Winter War. The former administrative structure, the intrinsic to Finish counties, was generally preserved on the newly zoned areas of Karelian-Finnish Union Republic. No significant changes were needed to convert the annexed Finnish counties into Soviet districts. Regretfully, new administrative boundaries between KFSSR and the Leningrad region on the territory of Karelian Isthmus disrupted its unity and complicated the process of district zoning on the territories of Leningrad region.