The Mentawai Strait is the body of water between Sumatra and Mentawai Islands, Indonesia. Sumatra (also spelled Sumatera) is the sixth largest island in the world (approximately 470,000 km²) and is the largest island entirely in Indonesia (two larger islands, Borneo and New Guinea, are partially in Indonesia). ... The Mentawai Islands are a chain of islands off the west coast of Sumatra in Indonesia. ...
As a part of Southeast Asia it is unconvincing to posit that stasis and isolation are the primary characteristics of the history of the Mentawai islands prior to their entry into the written, and therefore by definition, historical record.
In relation to the Mentawai islands, not a great deal of archaeological work has been carried out and therefore a detailed knowledge of the area' prehistory is yet to materialize.
To hold, therefore, that the contemporary inhabitants of the Mentawai islands are somehow "primitive" relics of a bygone era that have only recently, or are only now, opening up to the rest of the world and beginning to change is a position not well supported by the available evidence.