The Mandarese, historically a seafaring group and professing Islam since the 17th century (with a population of approximately 1 million), are an Indonesian ethnic group from the province of West Sulawesi (Sulawesi Barat). But their cultural heartland is constituted by the southern part of the island of Sulawesi ( the undivided province of Sulawesi Selatan) that was bifurcated into Sulawesi Selatan (South Sulawesi) and Sulawesi Barat (West Sulawesi) in 2004. The Mandarese speak Mandar, a relative of the Toraja- Sa'dan language that belongs to the Northern sub-group of the South Sulawesi group of languages of the Malayo-Polynesian group of the Austronesian language family.