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