Japan The population of Japan from a 1996 estimate is about 125,449,703 people. The population density is of about 332 persons per sq. km or 860 people per sq. mi. About 78 percent of the people live in urban areas. Japan has an area of 377,688 sq. km. The Japanese Islands extend in an irregular crescent from the island if Sakhalin (Russia) to the island of Taiwan. Japan proper consists of the large islands of Hokkaido, the northernmost; Honshu, the largest, called the mainland; Shikoku; and Kyushu, the southernmost. The combined area of these three islands is about 362,000-sq. km. Tokyo is Japan's capital an