The Yakan are probably the original inhabitants of Basilan, and may once have inhabited the whole island. Later the coastal areas were occupied by Sama and Tausug from the Sulu Islands and, more recently, some Christian Filipinos settled not far from the coast, where they established rubber and coconut plantations. The sultan of Sulu once claimed Basilan as part of his possessions. Christian occupation started when the Spanish colonial government established a fort at Isabela on Basilan's northwest coast in 1842. In the 1870s the Yakan were conquered by a Christian Tagalog, who had escaped from a penal colony in nearby Mindanao. After some resistance the Yakans recognized him as their leader, with the title of datu. He adopted Islam, but he also restricted the hostilities between Yakan and Christians. He was succeeded first by a nephew, later by that man's son, who in 1969 was proclaimed sultan of Basilan. The unrest in the southern Philippines in the 1970s hit the Yakan very badly. In the early seventies a considerable part of Basilan was controlled by the rebels, and many Yakans were evacuated for some years. The Yakan are in many respects culturally related to other Muslim groups (Moros), not merely in religion. There has been contact with the Tausug and Sama, and especially with the Sama there is much cultural similarity. However, the Yakan have their own identifiable culture.