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  British Indian Ocean Territory::  

6 00 S, 71 30 E & 7 20 S, 72 25 E
indigenous inhabitants
the laws of the UK
54,400 sq km


Government and politics

As a territory of the United Kingdom, the head of state is Queen Elizabeth II. There is no Governor appointed to represent the Queen on the territory, as there are no native inhabitants. The head of government is the Commissioner, currently Tony Crombie (since January 2004, replacing David Ross MacLennan) and Administrator Tony Humphries (since February 2005, replacing Charles A. Hamilton), all of whom reside in the UK.

The laws of the territory are based on the constitution, set out in the British Indian Ocean Territory (Constitution) Order 2004. Applicable treaties between the United Kingdom and the United States govern the use of the military base. The United States are required to ask permission of the United Kingdom if they are using the base for offensive military action.

The UK has an agreement with Mauritius to return the territory in the event that they are no longer required for defence purposes.

Ethnic groups

British 95.88%, others 4.12%

The History

The Islands of Chagos Archipelago were discovered by Vasco da Gama in the early sixteenth century, then claimed in the eighteenth century by France as a possession of Mauritius. However, in 1810, Mauritius was captured by the United Kingdom, and France ceding the territory in the Treaty of Paris (1814). Agricultural workers migrated to the Islands in the late 19th century, settling on the main island of Diego Garcia and establishing copra plantations.

In 1965, the United Kingdom split the Chagos Archipelago from Mauritius, and the islands of Aldabra, Farquhar and Desroches (Des Roches) from the Seychelles to form the British Indian Ocean Territory. The purpose was to allow the construction of military facilties for the mutual benefit of the United Kingdom and the United States. The islands were formally established as an overseas territory of the United Kingdom on November 8, 1965. On June 23, 1976, Aldabra, Farquhar and Desroches were returned to Seychelles as a result of it attaining independence. Subsequently, BIOT has consisted only of the six main island groups comprising the Chagos Archipelago.

The creation of BIOT has been subject to legal controversy, as some legal opinions from international law experts say that the decision to separate the BIOT from Mauritius was illegal because international law does not allow the dismembering of a country before independence. However the decision was taken with the full agreement of the Mauritius Council of Ministers

In 1966, the British Government purchased the privately owned copra plantations, and closed them down, and removed the entire population (known as the Ilois, or Chagossians) of Diego Garcia to Mauritius. In 1971, the United Kingdom and the United States signed a treaty, leasing the island of Diego Garcia to the American military for the purposes of building a large air and naval base on the Island. The deal was important to the United Kingdom, as the United States agreed to give them a substantial discount on the purchase of Polaris nuclear missiles in return for the lease. The strategic location of the Island was also significant at the gateway of the Indian Ocean, and to counter any Soviet threat in the region.

View of Diego Garcia, showing military base.Work on the military base commenced in 1971, with a large airbase with several long range runways constructed, as well as a harbour suitable for large naval vessels. Although classed as a joint UK/US base, in practice it is mainly staffed by the American military, although a small British garrison is maintained at all times, and Royal Air Force long range patrol aircraft are deployed there. The United States Air Force used the base during the 1991 Gulf War and the 2001 war in Afghanistan, as well as the 2003 Iraq War.

During the 1980s, the Mauritian Government asserted a sovereignty claim on the territory, citing the 1965 separation as illegal under international law, despite their apparent agreement at the time. The Seychelles also launched a sovereignty claim on several of the Islands.

The Ilois, who now reside in Mauritius and the Seychelles have continually asserted their right to return to Diego Garcia, winning an important legal victory in the British High Court of Justice in 2000. However, this judgement was overturned by Order-in-Council in June 2004. On May 11, 2006 the British High Court ruled that these Orders-in-Council were unlawful, and consequently that the Ilois were entitled to return to the Chagos Archipelago. It remains to be seen whether the British Government will appeal, and when or how the judgment might be implemented in practice.

The Ilois were granted the right to visit Diego Garcia on April 3, 2006 for humanitarian purposes, including the tending of the graves of their ancestors.


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