The Jarawas have a history as traditional hunter-forager-fishermen, and have also had reputations as warriors and uncompromising defenders of their territory. Before the 19th century, the Jarawa homelands were located in the southeast part of South Andaman Island and nearby islets. With the establishment of the initial British settlement, these are suspected to have been largely depopulated by disease shortly after 1789. The Great Andamanese tribes were similarly depopulated by their overuse of alcohol and opium after their introduction, leaving open the western areas which the Jarawa gradually made their new homeland. The spreading of opium and alcohol was to some extent sponsored by the colonial authorities in order to depopulate the Jarawa. The immigration of mainland Indian and Karen (Burmese) settlers, beginning about two centuries ago, accelerated this process.