The Muslim population has been steadily increasing in South Korea since the introduction of the Islamic faith shortly after the Korean War. The Muslim (both Korean and foreign born) community is centered around Seoul, where the first large 20th-century mosque was built in 1976 using the funds of the Malaysian Islamic Mission and other Islamic countries.
In addition to fewer than 30,000 indigenous Korean Muslims, there has been a slow but evident growth of South Asian (Pakistani), Middle Eastern (i.e. Iranian and Iraqi) and Malaysian immigration to South Korea, the majority being Muslims, during the 1990s and 2000s, usually arriving as guest workers to the country. There are more than 1 million foreign workers from Muslim countries, particularly from Bangladesh and Pakistan. In total, there are up to 35,000 Muslims in South Korea.
It is believed that there is no significant presence of Islam in North Korea, where autonomous religious activity in general is almost non-existent.
During the Korean War, Turkey sent a large number of troops to aid South Korea under the United Nations command, called the Turkish Brigade. In addition to their contributions on the battlefield, the Turks also aided in humanitarian work, helping to operate war-time schools for war orphans. Shortly after the war, some Turks who were stationed in South Korea as UN peacekeepers began teaching Koreans about Islam. Early converts established the Korea Muslim Society in 1955, at which time the first South Korean mosque was erected.