More than one in 100 people residing in Japan is a foreign national -- but not all of them are immigrants or expatriates from overseas. Koreans are the largest foreign ethnic group in Japan, numbering some 635,269 persons (or 37.7 percent) of a foreign population put at around 1.7 million. Many are the Japanese-born second-, third- or fourth-generation descendants of those brought here as forced laborers during the 1910-45 Japanese annexation of the Korean Peninsula.

In many cases native speakers of Japanese, these zainichi (living in Japan) Koreans comprise 80 percent of those holding permanent-residence status in this country. The presence of these Koreans as foreign nationals is a product of Japan's policy of conferring citizenship on grounds of bloodline (jus sanguinis), and not simply to those born on the state's soil (jus solis).

The second-largest foreign population in Japan is of Chinese -- at 19.9 percent, or 335,575 individuals -- and Chinatowns have been long established in Yokohama, Kobe and Nagasaki. Although some prominent officials may proclaim the threat posed by Chinese organized crime, it is study that brings many Chinese here: There are roughly 77,000 Chinese students and 2,000 professors and scholars at universities in this country.