Islam is a minority religion in Japan. In the absence of official statistics on Muslims in Japan, demographic estimates range from between 70,000 to 120,000 Muslim residents with about 10 percent of that number being Japanese. The majority of estimates of the Muslim population in Japan are around 100,000. According to some sources, there were 30,000 Muslims in Japan in 1982.
In the 14th century, Japan was contacted by Islam via merchants from Arab countries and China. Another important contact was made in 1890 when the Ottoman Empire dispatched a naval vessel to Japan for the purpose of starting diplomatic relations between the two empires as well introducing Muslims and the Japanese to each other. This naval vessel, the Ertuğrul, capsized and sank with 609 people aboard, drowning 540 of them, while returning home. In the late 1870s, a biography of the Prophet Muhammad was translated into Japanese. This helped Islam spread and reach the Japanese people.
Islam was thought to come to Japan in the early 1900s when Muslim Tatars were escaping Russian expansionism. Hundreds of Tatar Muslim refugees from Central Asia and Russia came to Japan during the wake of the October Revolution in the early 1900s. These Muslims were given asylum in Japan and settled in several main cities around Japan, forming small communities. Some Japanese converted to Islam through contact with these Muslims. During World War II, over 100 books and journals on Islam were published in Japan.
With the oil crisis years in the 1970s, the Japanese mass media had given space to the Muslim world in general, and the Arab world in particular, after realizing the importance of these countries for the Japanese economy. In the 1960s hundreds of Pakistani and Bangladeshi Muslims migrated to work in Japan and became settled. According to the International Organization for Migration (IOM), the population of foreign workers in Japan has nearly doubled in the last 20 years, reaching more than 2 million at the end of 2011. However, Muslims from Pakistan and Bangladesh increased in the late 1980s as visa waiver programs were introduced by the Japanese government. There are some 60 Muslim communities alive in Japan, 40 of them non-Japanese.