Chagos Archipelago (the)

Geography of the Archipelago


 The Chagos archipelago, the main island being Diego Garcia, is located at the heart of the Indian Ocean, half-way between Africa and Indonesia, 7° south of the equator and 500 km south of the Maldives. The archipelago, covering approximately 15,000 km2, of which only 56 km2 are firm land, consists of more than 50 islands, shoals, coral reefs and banks, grouped into 7 atolls, the most of important of which are Peros Banhos, the Salomon islands, the Great Chagos Bank – ​​ the largest on the planet – as well as the Eagle Islands, the Three Brothers, Danger Island, Nelson’s Island, the Edgmont Islands and Diego Garcia to the southeast. It is regarded as one of the richest marine ecosystems of the world with outstanding ecological values. In particular, the Chagos Conservation Trust (n.d.) describes the archipelago as “the most pristine tropical marine environment surviving on the planet”.





History of the archipelago


The archipelago was discovered by the Portuguese navigator, Pedro Mascarenhas, in 1512, but the islands remained unpopulated until late in the 18th century when the first plantations were established on Diego Garcia by a few French Île-de-France (now Mauritius) land owners with slaves from Mozambique and Madagascar, as well as a few free Blacks. ​​ In 1810, the British seized Mauritius, and obtained its ‘minor dependencies’ (Seychelles, Rodrigues and Chagos) by the Treaty of Paris of 1814. In 1835, Great Britain abolished slavery and the Chagossian slaves became “contract workers”. A number of Malay, Chinese and Indian indentured workers were also imported. During the 19th century a plantation society developed on Chagos, much as elsewhere in the Mascarenes, the Antilles, etc. The basic economic source was the coconut tree, either to extract coconut oil on site or to make copra. In 1880, the population of the archipelago was approximately 760 souls, the great majority being Creole. In the ensuing years, employees from Mauritius or Seychelles settled on the islands, thus increasing the local population to which they quickly assimilated. The Chagossians continued to work for the oil extraction company, many also doing some fishing, gardening or raising small livestock, but never becoming owners of their plots or their meager homes. Over two centuries, the Chagossians developed into a distinct people with its own Creole dialect (related to both Mauritian and Seychellois Creole), its own music, culinary specialties and other aspects of culture.


Deportation of the Chagossians


In 1962, the Chagos Agalega Company of Seychelles bought all of the coconut plantations of the archipelago from the Mauritian Société huilière de Diego et Peros. Three years later, after years of secret negotiations with its Mauritian colony and in contravention of the United Nations decolonization rules, the United Kingdom promised Mauritius its independence but by an ‘Order in Council’, created the British Indian Ocean Territory, which included not only the Chagos archipelago but also the Aldabra, Farquhar and Des Roches islands, then under Seychelles control. In compensation, the UK offered the sum of £3 million to the colonial government of Mauritius and a new airport for Seychelles. In 1966, again by a secret accord, the UK signed a 50-year (20-year renewable) free ‘lease’ on Diego Garcia to the United States, where they intended to build an important naval support facility. Before agreeing to the lease, the Americans insisted that the population of the whole archipelago be ‘removed’, to which the British readily agreed. As a counterpart, the Americans reduced a British contract on the purchase of Polaris missiles by £11 million. It is to be noted that between 1965 and 1968, the United Nations General Assembly (UNGA) adopted three resolutions calling upon the UK government to take no actions which would dismember the Territory of Mauritius and violate its integrity.

 In 1967, the British government bought all the Chagossian plantations for the sum of £600,000. The following year, Mauritius became independent. Beginning in1968, by British decision, any Chagossian leaving the islands for medical reasons or for visiting relatives in Mauritius was refused a return passage, which de facto condemned more than 400 Îlois to exile. At the same time, the British authorities willingly restricted importation of medical and food supplies to the islands and attempted to have everyone believe that there never had been any permanent population on the islands and that the Chagossians were merely temporary contract workers.

From 1971 to 1973, the remaining 2,000 Chagossians were forcefully loaded onto boats headed either for Mauritius or Seychelles, where they were left to fend for themselves and were obliged to live under inhuman conditions. Incapable of finding work suitable to their training, many fell prey to alcoholism, prostitution and petty crime. The British government offered the paltry sum of £650,000 to the Mauritian government to help relocate the Chagossians, but it took more than five years for them to receive the money, without the accumulated interest. In 1982, following a hunger strike and a lawsuit led by a group of Chagossians, the British government granted them the sum of £4 million in compensation for their hardship and the Mauritian government offered them land worth £1 million, but in order to obtain their share, they were forced to sign a document, written exclusively in English, which forever extinguished any possibility of their returning to the islands. Most Chagossians, being illiterate and speaking only Creole, were therefore unable to understand what they were signing. In the meantime, the Americans were developing their air-naval base on Diego Garcia. Originally dubbed ‘Footprint of freedom’ (currently named Camp Thunder Cove), where some 2,500 military personnel and contract workers (mostly from Mauritius or the Philippines, none from the Chagos) were deployed. Due to its location, the Diego Garcia base was instrumental in both the Iraq and Afghanistan conflicts and presently represents America’s vital defense outpost for the Indian Ocean and Southeast Asia.


Chagossian and Mauritian Legal Battles

 Since their deportation, the Chagossians have unceasingly fought on a number of fronts to allow their return to their homeland, bringing lawsuits to British and American courts. In turn, Mauritius has lobbied and fought on several international fronts for recognition of its sovereignty over the archipelago.

​​ In 2000, the English and Welsh High Court of Justice declared that the deportation of the Chagossians during the 1970s had been illegal and that they had the right to return to their islands, with the exception of Diego Garcia. However, three years later, the same High Court reversed its decision, estimating that the Chagossians had been amply compensated for their expulsion. The same year, a lawsuit brought to the US District Court for the District of Washington by the Chagos Refugees Group (CRG) ended in favour of the United States.

In 2002, all Chagossians born on Chagos, as well as their children, obtained British citizenship and many of them, then living in Mauritius, Réunion or Seychelles, immigrated to England, most settling in and around the town of Crawley, near Chadwick airport, south of London. It is estimated that some 5,000 Chagossians currently live in the UK.

In 2004, a new Order in Council abolished their right of return to the islands. Following an appeal by the GRC, the order was overturned by the Division Court, and later by the High Court of Justice.

In 2008, the highest judiciary instance of the country, the judicial committee of the House of Lords, overturned the High Court decision, thus theoretically ending any possible UK legal recourse for the Chagossians. That same year, the British government earmarked the sum of £40M for Chagossians in the UK, Seychelles and Mauritius. The funds were to cover support for improved access to health, education, employment and cultural conservation. The British support package also included visits to the various islands of the archipelago, however it seems very little of the promised money has actually been spent.

 In October, 2009, J.-M.G. Le Clézio wrote a public letter in Le Monde, addressed to President Obama, who had recently been awarded the Nobel Peace Prize, in which he asked that the Chagossians be allowed “to return to their native land, to work (and why not on the military base?), and to honor their dead. It would not be an act of charity, but of justice.” (Le Clézio, 2009) (Our translation). The letter was never answered.

In 2010, the UK established a Marine Protected Area (MPA) of some 64,000km2 covering the Chagos archipelago, but excluding Diego Garcia. All fishing or exploitation of any kind within the MPA was henceforth illegal. According to a number of documents revealed by the now famous Wikileaks, the Foreign Office in London was said to have suggested to the American government that the establishment of the MPA would make the return of the Chagossians quite impossible. The Mauritian government rapidly brought a suit against the UK at the UN’s Permanent Court of Arbitration (PCA), contesting the legality of the MPA, based on the UN’s Convention on the Law of the Sea (UNCLOS). The same year, the European parliament adopted a resolution recognizing the illegality of the Chagossian deportation and proposed that the European Court of Human Rights determine the merits of the suit brought by the GRC in 2007.

In 2012, the European Court of Human Rights refused to hear the suit brought by the GRC five years earlier, invoking a number of technical legal arguments, while indicating that the Chagossians had already been amply compensated for their troubles. During the same year, an international petition launched by the GRC on the American White House We the People website, pleading the Chagossians’ cause, gathered more than 28,000 signatures. Nevertheless, the White House replied that it was powerless to act and that the UK had sole authority on the Archipelago, including Diego Garcia.

In 2013, the British High Court ruled favorably on the legality of the MPA. That same year, Le Clézio wrote a second article, published in Libération, deploring the Court of Human Rights’ ruling: “In truth, however iniquitous it may be, the European Court of Human Rights’ ruling was predictable. It demonstrates the fragility of international forums in matters of justice. When it has to pronounce itself on litigious questions, the European Court behaves much like an ordinary tribunal, taking refuge behind a procedural code and arguing about inadmissible judicial elements, as it would in a simple litigation between individuals. In so doing, it is not in contradiction with the spirit of the law, but it is totally so with the spirit of human rights […] The European Court of Human Rights has rendered its decision, in the indifference on the part of the world’s powers. What matters a handful of Ilois, small farmers, fishermen casting their lines in the lagoon, when strategic and military interests are at stake, and that these faraway islands, lost in the middle of the Indian Ocean, can be transformed at low cost into one of the most operational bases in the world…” (Le Clézio, 2013) (Our translation)

In 2015, the PCA unanimously ruled that the MPA over the Chagos Archipelago had been created in violation of international law under the UNCLOS. However, the PCA ruling did not address the question of sovereignty over the archipelago.

Also in 2015, Olivier Bancoult, leader of the GRC, launched an appeal to the Supreme Court contesting the House of Lords’ 2008 decision, which the Court accepted to hear. The following year, the Court rejected Bancoult’s appeal.

In November 2016, the British government extended the ‘lease’ of the US military base on Diego Garcia for a further twenty years. The Foreign and Commonwealth Office declared that Chagossians would not be allowed to return “on the grounds of feasibility, defence and security interests, and costs to the British taxpayer.” However, the government renewed its promise of £40 million to the Chagossians over a ten-year period.

In June 2017, a majority of countries at the UN General Assembly (UNGA) voted to ask the International Court of Justice (ICJ) to give an advisory opinion on the separation of the Chagos Archipelago from Mauritius before its independence in the 1960s.

In February 2019, the ICJ at The Hague issued a non-binding advisory opinion rejecting the UK’s claim of sovereignty over the Chagos Islands and ruling that the islands rightfully belonged to Mauritius. The ICJ further advised that all members of the UN were obligated to work toward the decolonization of Chagos. The UK took no notice. Three months later, 116 states voted at the UNGA to endorse the ICJ’s decision and called upon the UK government to transfer the archipelago to Mauritius within six months. Again, the UK insisted that both the ICJ ruling and the UNGA vote were merely advisory and non-binding. The government declared that it was still the lawful authority and that if and when it no longer needed the archipelago for its defence purposes, it would ‘cede’ the territory to Mauritius. The American reaction was that it “unequivocally supports UK sovereignty. The specific arrangement involving the facilities of Diego Garcia is grounded in the uniquely close and active defense and security partnership between the United States and the UK. It cannot be replicated. » As of November 2019, since the UK has not complied with the UNGA decision, it has been branded as an ‘illegal colonial occupier’ by Mauritius.

In May 2020, the Court of Appeals in London refused the GRC’s appeal concerning the right to return and the matter of the £40M promised to the Chagossians, arguing once again the economic non-feasibility of an eventual return to the islands and that as far as the problems concerning the distribution of the financial package, they were due to the lack of cooperation on the part of the Mauritian government as long as the matter of sovereignty over the Chagos was not resolved. Olivier Bancoult, leader of the GRC, proceeded to appeal the decision to the British Supreme Court.

In June 2020, Mauritius initiated arbitral proceedings against the Maldives at the International Tribunal for the Law of the Sea (ITLOS), in order to delimit the maritime boundary between the Maldives and the Chagos archipelago.

In January 2021, ITLOS confirmed the legitimacy of Mauritius’ claim to the archipelago, calling Britain’s continuing administration of the islands unlawful and criticized its failure to hand the islands back to their rightful owner, Mauritius. The binding ITLOS decision puts both the UK and the USA in a difficult position. For the US, the decision implies that it is running a military base on territory that is illegally occupied by a state with no claims to it under international law. Furthermore, both countries, have repeatedly invoked the principle of “rule-based order” and both have severely chastised China for ignoring a recent ITLOS ruling in favor of the Philippines concerning the South China Sea, all the while ignoring the ITLOS ruling on Chagos. On the other hand, leasing Diego Garcia to the Americans also poses a problem for Mauritius, since it is signatory to the Pelindaba Treaty (African Nuclear-Weapon-Free Zone Treaty). If Mauritius were to become sovereign over the archipelago, including Diego Garcia, it could no longer station nuclear weapons on its territory, including those carried by foreign ships or aircraft. As well, the Mauritian ambassador to the UN has stated that when Mauritius regains sovereignty, the Chagossians would be rehabilitated to three outlying islands, at least 100 miles away from Diego Garcia, which would be contrary to most Chagossians’s wishes of returning to Diego Garcia itself.

Since October, 2020, the UN official world map indicates the Chagos Archipelao to be Mauritian territory. Also, the Universal Postal Union (UPU), a UN specialized agency for postal matters, formally recognized the Chagos Archipelago as an integral part of the territory of Mauritius. As a result, the UPU will no longer register, distribute or forward postage stamps issued by the so-called ‘British Ocean Territory.


The Present Situation


The next step in the fight over the archipelago will occur at the Indian Ocean Tuna Commission (IOTC), the intergovernmental authority established by the UN Food and Agriculture Organization in 1966 to regulate fishing in the region. Mauritius is lobbying to expel the UK from the IOTC, claiming that the BIOT does not legally exist and therefore that the UK is not Indian Ocean coastal state. The UK is undoubtedly in a difficult situation since the IOTC will be hard put to ignore the ITLOS ruling, since both are UN legal authorities.

On February 14, 2022, a small delegation of Chagossians, led by Olivier Bancoult of the GRC and by the Mauritian ambassador to the UN, landed on Peros Banhos, where it raised the Mauritian flag, thereby declaring Mauritian sovereignty over the archipelago, in defiance of UK’s territorial claims. Britain’s Foreign Office replied by stating that the UK “has no doubt as to our sovereignty over the BIOT, which we have held continuously since 1814.”

The battle for the return of the Chagos islands to Mauritius and that of the Chagossians’ right to British citizenship as well as their right to return to their islands must not be confused. The most recent development on this front is the Nationality and Borders Bill, recently presented to the British parliament. If passed, it would allow the grand-children and great-grand-children of those Chagossians born on the islands to obtain British citizenship. Currently they are considered as clandestine.

 The stakes over the sovereignty of the Archipelago are not solely a question of justice and rights for Mauritius; they are also financial. Needless to say, when Mauritius recovers the islands, and notably Diego Garcia, the 99-year lease which it promises to sign with the Americans will provide millions of dollars annually. Furthermore, the Internet Assigned Numbers Authority (IANA), the organism which attributes internet domain names, assigned the domain .io to a rich British businessman, involving millions of dollars, and it now belongs to Ethos Capital, an American investment firm. If Mauritius regains sovereignty over the Chagos archipelago, it would then inherit legal rights to the .io domain, as well as the huge annual profits that this address brings.



Robert Papen

Translated by the author


Further Readings


Alexandre, C. et K. Koutouki. 2014. “Les déplacés du Chagos, retour sur la lutte de ces habitants pour récupérer leur terre ancestrale”, Revue québécoise de droit international, vol. 27,2 :1-26.

Allen, S. and C. Monaghan. 2018. Fifty years of the British Indian Ocean Territory: Legal perspectives. Cham, Switzerland, Springer International Publishing.

Benson, P. 2012. A lesser dependency. London, Alma Books.

Bruno, J.-F. 2017. “Géographies insulaires, frontiers territoriales et écologies politiques : Rodrigues et les Chagos, ces ‘étrangères’ de la nation mauricienne ”.  Nouvelles Études Francophones, vol. 32,2 : 124-139.

Bashfield, S. 2020. “Mauritian sovereignty over the Chagos Archipelago? Strategic implications for Diego Garcia from a UK-US perspective”. Journal of the Indian Ocean Region, vol. 16,2: 166-181.

(The) Chagos Archipelago. n.d.

Chagos Conservation Trust. n.d.

Chagos Support Group. s.d.

Chagossian Voices. n.d.

Evers, S. & M. Kooy (eds.). 2011. Eviction from the Chagos Islands. Displacement and Struggle for Identity Against Two World Powers. Leiden, Brill.

(The) Guardian. 2021. UN court rejects UK claim to Chagos Islands in favour of Mauritius. January, 28, 2021.

Güzul, Mehmet. 2018. “The Chagos Archipelago Case in the International Court of Justice”, Ankasam/Bölgesel Araşlirmalar Dergesi: 119-151.

Harris,P. 2021. “The case for decolonizing the Chagos Islands: A response to Bashfield”. Journal of the Indian Ocean Region, vol. 17,2: 224-229.

Jeffrey, L. 2013. Chagos Islanders in Mauritius and UK. Forced displacement and onward migration. Manchester, Manchester University Press.

Laurent, C. 2020. Rivage de la colère. Paris : Pocket.

Le Clezio, J.-M.G. « Lavez l’injustice faite aux Chagossiens », Le Monde, 17 octobre, 2009.

Le Clezio, J.-M.G. « Les Îlois contre le Royaume –Uni, suite et fin? », Libération, 14 mai, 2013.

Mandrilly, A. 2006. Les Exilés de l’océan Indien (Îles Chagos). Licence en anthropologie. Université Bordeaux II.

Patel, S. 2005. Le silence des Chagos, Paris, Éditions de l’Olivier.

Pierre S. J.-N. 2021. Absolutely Must Go. ​​ (Film documentaire sur la lute des Chagossiens).

Thakkar, C. 2021. Overcoming the Diego Garcia stalemate. War on the Rocks, July, 2021.

Vine, D. 2009. Island of shame : The secret history of the US military base on Diego Garcia, Princeton, Princeton University Press.

Wenban-Smith, N. and M. Carter. 2016. Chagos: A history. Exploration, exploitation, expulsion. Chagos Conservation Trust, York, UK, YPD Books.