Archaeological findings have revealed that Manipur was inhabited by pre-historic man since stone age. Cultural relics of pre- and post-historic periods are found from many caves and open-air sites. Mention may be made of the discovery of caves at Kangkhui (Ukhrul District), Sangbu (Chandel District), Tharon (Tamenglong District), Nongpok Keithelmanbi (Senapati District), Mongjam (Imphal District) and Wangoo (Bishenpur District). The palaeolithic man lived in caves while the Neolithic lived in open-air sites. Neolithic man reached the Manipur Valley not later than 2000 B.C. Recent archaeological findings at Tharon cave and Napachik etc. in Manipur point to the existence of a Mon-Khmer speaking Australoid-Mongoloid people who migrated to this land before the arrival of the Tibeto-Burman speakers.
When Tai origin is questioned, well-established proto-historic and historic relationships between the Meiteis, Mon-Khmer and the Tai are supposed to have produced Tai influence on the language and culture of the Meiteis.