Western Russia depicted just shortly after the October Revolution and before Stalin decides to move populations according to his whims.
It was compiled in Lausanne and a full version with better resolution can be seen here https://upload.wikimedia.org/wikipedia/commons/7/71/Ethnographic_map_of_Europe_-_by_lithuanians_Sudare_and_J_Gabrys_-_Lausanne_-_1918_AD.jpg