A horrible part of Russia’s history is the pogroms that killed many Jews. Information on pogrom victims is scattered on many websites.
A Jewish organization has created a searchable database on many thousands of pogrom victims from 1918-1921 in the areas considered Russia at that time. The database is still being updated, but information from more than 1,500 settlements can be found on the database. (A detailed explanation of pogroms can be found here.)