This map visualizes data from the 1926 First All-Union Census of the Soviet Union, showing the percentages of residents categorized as ethnically Bulgarian in each district (raion) of the Ukrainian Socialist Soviet Republic.
The darker shades of color indicate the higher percentages. The darkest shade indicates percentages of 66.6-74.3 percent, while the lightest shade indicates percentages below 4.5 percent.
The boundary lines indicate those of the March 1, 1927 administrative division.
All-Union 1926 Census (Vsesoiuznaia perepis' naseleniia 1926-ogo goda). Moscow: Central Statistics Department of the USSR.1928-1935.