The Chagos and Maldives chain of islands was created after the Indian plate slid north, millions of years ago, crumpling up the Himalayas in front of it. Upwelling lava from a hotspot deep in the earth’s mantle created the bases of these islands; those of Chagos were pushed up 45 million years ago. The islands’ lava cores then began their long, slow subsidence, while reefs from the remains of living coral built up around them. The hotspot has moved position relative to the Indian Ocean and is now situated under the island of Reunion. Amazingly, the coral under Diego Garcia is about a mile deep. In the late 19th century Charles Darwin drew extensively on scientific surveys of the Chagos archipelago for his theories on coral reefs.
The Chagos Islands were uninhabited when Europeans first arrived in the 1500s. In 1793 a French colony was established consisting of a slave-based plantation economy. In 1814 the islands were ceded to Britain by France as part of the Treaty of Paris, and they have been British territory since that time. Following emancipation by Britain in 1840, some descendants of the former slaves, along with newly contracted immigrants, stayed on the Chagos to work there. By the middle of the 20th century, the coconut industry had become unprofitable and was closing down. Following the decision in the 1960s that the islands should be set aside for defence purposes, the remaining plantations were closed and the islanders who were still in the Chagos (estimates vary between 1,200 – 2,500 people) were removed to Mauritius and the Seychelles. Although many former Chagos islanders and their children still live in Mauritius and the Seychelles, around 2,000 have since moved to the UK following their designation as full British Citizens by The British Overseas Territories Act of 2002.
Apart from the island of Diego Garcia, where there are military and support personnel (including a very small number of Diego Garcians and other Chagossian community members), the other 54 tiny coral islands, adding up to only 16 square miles in total, are uninhabited – and most have always been so. Due particularly to climate change, the islands, which are mainly less than two metres above sea-level, are increasingly vulnerable to erosion, flooding and other effects of sea-level rise.
Compensation has twice been paid by the British government for the benefit of the displaced Diego Garcians and other Chagossian communities. In 1973 £650,000 was paid to the Government of Mauritius, and in 1982 £4 million was paid into a Trust Fund. In today’s terms, these payments are worth approximately £14.5 million. In addition, about £1 million worth of land in Mauritius was reportedly made available to the Diego Garcians and other Chagossian groups. There is some controversy surrounding compensation intended for the Diego Garcians and other Chagossian communities residing in Mauritius however, as although this compensation was certainly paid, there is evidence that not all of it reached the intended recipients. Chagossian communities who had been moved to the Seychelles were compensated indirectly through construction projects.
Over the past decade, Diego Garcians and other Chagossian groups have brought a number of claims against the UK and US Governments for additional compensation and the right to return to the Islands. In 2008, a judgment by the Law Lords upheld the British government position, which states that there is no right of abode in the Chagos and that anyone wishing to visit needs authorisation. In 2012, the Diego Garcians and other Chagossian communities took their case to the European Court of Human Rights in Strasbourg. The Court rejected the case on the grounds that it was inadmissible.
The Territory is administered by the UK Government through the BIOT Administration, based in London. There are no economic activities on the islands. Ongoing UK/US Agreements regulate the use of the Territory for defence purposes.