In this world map, you can check at a single glance which countries have more people with the surname Koriu. As you can see, it's effortless to notice which countries have a higher number of people carrying the Koriu surname.
Thanks to this world map that shows the density of people with the surname Koriu in different countries, you can get an idea not only of the popularity of the surname Koriu in each country but also of the different migrations of people surnamed Koriu.