The ancestral population of modern Asian people has its origins in the two primary prehistoric settlement centres – greater Southwest Asia and from the Mongolian plateau towards Northern China. Migrations of distinct ethnolinguistic groups have probably occurred as early as 10,000 years ago. However, about 2.000 BCE early Iranian speaking people and Indo-Aryans have arrived in Iran and northern Indian subcontinent. Pressed by the Mongols, Turkic peoples often migrated to the western and northern regions of the Central Asian plains. Prehistoric migrants from South China and Southeast Asia seem to have populated East Asia, Korea and Japan in several waves, where they gradually replaced indigenous people, such as the Ainu, who are of uncertain origin. Austroasiatic and Austronesian people est