In this world map, you can check at a single glance which countries have more people with the surname Johnstone. As you can see, it's effortless to notice which countries have a higher number of people carrying the Johnstone surname.
Globalization can make the surname Johnstone be found in almost every country around the globe, but being able to see the density of people residing in a country with the surname Johnstone greatly aids all those who seek a deeper knowledge about the surname Johnstone.