Marxist USSR Genocide, 1923-1928, 2.2 million killed.
This video covers the USSR 1923-28 NEP period. NEP was Lenin's New Economic Policy. Statistician RJ Rummel is cited thoroughly, with his conservative estimate median of 2.2 million with a high of 4.8 million, along with overall estimates from 1930's to 1950's as up to 70 million killed, and various sources, including Soviet scientists.