Mentawai Islands in the context of "West Sumatra"

Sumatra (/sʊˈmɑːtrə/) is one of the Sunda Islands of western Indonesia. It is the largest island that is fully within Indonesian territory, as well as the sixth-largest island in the world at 482,286.55 km (182,812 mi.), including adjacent islands such as the Simeulue, Nias, Mentawai, Enggano, Riau Islands, Bangka Belitung and Krakatoa archipelago.

Sumatra is an elongated landmass spanning a diagonal northwest–southeast axis. The Indian Ocean borders the northwest, west, and southwest coasts of Sumatra, with the island chain of Simeulue, Nias, Mentawai, and Enggano off the western coast. In the northeast, the narrow Strait of Malacca separates the island from the Malay Peninsula, which is an extension of the Eurasian continent. In the southeast, the narrow Sunda Strait, containing the Krakatoa archipelago, separates Sumatra from Java. The northern tip of Sumatra is near the Andaman Islands, while off the southeastern coast lie the islands of Bangka and Belitung, Karimata Strait and the Java Sea. The Bukit Barisan mountains, which contain several active volcanoes, form the backbone of the island, while the northeastern area contains large plains and lowlands with swamps, mangrove forest and complex river systems. The equator crosses the island at its centre in West Sumatra and Riau provinces. The climate of the island is tropical, hot, and humid. Lush tropical rain forest once dominated the landscape.

The Mentawai (also known as Mantawai, Mentawei and Mentawi) people are the Austronesian people of the Mentawai Islands (principally Siberut, Sipura, North Pagai and South Pagai) about 100 miles from West Sumatra province, Indonesia. They live a semi-nomadic hunter-gatherer lifestyle in the coastal and rainforest environments of the islands and are also one of the oldest tribes in Indonesia. The Mentawai population is estimated to be about 64,000.

The Mentawai tribe is documented to have migrated from Nias – a northern island – to the Mentawai islands, living in an isolated life for centuries until they encountered the Dutch in 1621. The ancestors of the indigenous Mentawai people are believed to have first migrated to the region somewhere between 2000 and 500 BCE. The Mentawai language belongs to the Austronesian language family. They follow their own animist belief system called Arat Sabulungan, that links the supernatural powers of ancestral spirits to the ecology of the rainforest. When the spirits are not treated well or forgotten, they might bring bad luck like illnesses and haunt those who forgot them. Mentawai also have very strong belief towards objects they think are holy. The people are characterized by their heavy spirituality, body art and their tendency to sharpen their teeth, a cultural practice tied to Mentawai beauty ideals.