The Federal Security Service blocked access to the archives of Vyatka and Kazan provinces for the 18th-19th centuries for 140 years

With the help of revision tales (census of taxpayers), one can trace his genealogy up to 300 years ago, and the multiple analysis of genealogies would give a more complete picture of what happened in this territory under the imperial rule of those years.

Based on these documents, it is possible to create ethnic and linguistic maps of the population for those years. But who needs the population to know their history?