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