Q. Foreign-born population, which countries have the most? The United Nation's Department of Economic and Social Affairs, Population Division, tracks the total number of foreign-born people by nation. Find its Web site via a www.google.com search for "UN Population Division home page." Then select International Migration and find the International Migration Wall Chart. Which five countries have the most foreign-born residents in absolute terms? Which five countries have the greatest percentage of foreign-born residents? Why do the two lists differ so substantially?