The BIOT is an archipelago of 55 islands in the Indian Ocean, located south of India.  It is situated approximately halfway between Africa and Indonesia.  The islands form a semicircular group with an open sea towards the east.  The largest, Diego Garcia, is located at the southern extreme end.  It measures 60 square kilometres and accounts for almost three-quarters of the total land area of the territory.  Diego Garcia is the only inhabited island and is home to the joint UK-US naval support facility.  Other islands within the archipelago include Danger Island, Three Brothers Islands, Nelson Island, and Peros Banhos, as well as the island groups of the Egmont Islands, Eagle Islands, and the Salomon Islands.

In the late 18th century, coconut palm plantations were established on the island to produce copra for which slave labourers were brought in from Africa.  A small population lived in the archipelago, descendants of Mauritian labourers working the copra industry.  After an agreement was signed in 1966 between Britain and the United States, the US built a military base and forcibly evacuated all indigenous people; 1,200 from Diego Garcia, Ile du Coin, and Île Boddam were relocated to Mauritius, while others went to the Seychelles.  In 2000, the Chagos islanders won an appeal which restored their authority to live on the islands, and they received UK citizenship in the following year.  A 2008 court decision blocked their return.  Further complications arose after the 2010 establishment of the world’s largest marine reserve as the islanders’ commercial fishing capabilities, if they returned to the archipelago, would be curtailed, thus hampering their traditional livelihood.