Thanks to this world map that shows the density of people with the surname Bian in different countries, you can get an idea not only of the popularity of the surname Bian in each country but also of the different migrations of people surnamed Bian.
The quantity of people with the surname Bian that we can find in each country can help us discern the origin of the surname Bian, as logic tells us that the place with the most people surnamed Bian will be the country or area of origin of the surname Bian.