It seems to me that many Russian nationalists and neo-paganists currently believe that swastika was a Solar symbol or a symbol of fortune in ancient Slavic folklore.
There are multiple paintings by nationalist painters and other art that features swastika. Examples of articles which claim that swastika was an ancient Slavic symbol:
On the other hand the advocates of these theories explain the fact that swastika is not widely represented in museums of ancient Slavic culture by the claim that it is due to a conspiracy by the Bolshevicks/Jews/ZOG to hide items with swastika from the people.
So what is the reality. Was swastika ever a Slavic symbol before WWII?