Why is the UK's history with the Chagos Islands so controversial?

Diego Garcia, one of the islands in the Chagos archipelago. (AP)
Diego Garcia, one of the islands in the Chagos archipelago. (AP)

The UK has agreed to give up the sovereignty of a remote group of islands in the Indian Ocean to Mauritius, putting an end to decades of controversy over the British occupation.

The Chagos Islands sit in the centre of the Indian Ocean hundreds of miles south of India and had been controlled by the UK since 1814 after it was ceded to them by France.

Their strategic position has meant the UK has been unwilling to give them up for decades and keeping the joint UK-US naval base on the islands was central to the negotiations.

But the construction of this naval base has been marred in controversy for over 50 years and has been seen as a blackspot on the UK's modern approach to its colonial past.

The British initially used the islands as a plantation colony, with the slaves used to work the land not freed until 1840. Many chose to stay on the island and continued to work in the plantations, and it was from this population that the Chagossians came from.

In 1965, they were separated from the then self-governing territory of Mauritius to create the British Indian Ocean Territory. The UK operated the plantations on the islands but struggled to make any profit. This, in turn, made sustaining a local population increasingly expensive for the British.

The government decided to forcibly remove the population of roughly 2,000 between 1967 to 1973, sending them to Mauritius and the Seychelles to make way for the joint US-UK naval base. Many later moved to the UK after the government granted them citizenship.

The military base on Diego Garcia. (AP)
The military base on Diego Garcia. (AP)

Since the expulsion the UK has refused numerous requests to allow the islanders to return to their homes.

Chagossians have long complained they were effectively abandoned once they were dropped off, with many living in poverty and experiencing trauma.

Human Rights Watch claimed last year three crimes against humanity against the Chagossian people, including a continuing colonial crime of forced displacement, the prevention of their return home by the UK and their persecution by the UK on the grounds of race and ethnicity.

The United Nations’ highest court, the International Court of Justice, previously ruled the UK’s administration of the territory was “unlawful” and must end.

The islands were administered from Mauritius for most of the time both were part of the British Empire, until 1965 when they were separated to form the British Indian Ocean Territory. When Mauritius became independent in 1968, the Chagos were not included.

The Chagos Islands sit 800 miles from Mauritius but they have always claimed they were historically part of the same unit. They claim that for most of their history under the British Empire, they were the same territory and it was only in the three-year period when the UK was aware of Mauritius' desire for independence that they became separate legal units.

Protesters hold banners supporting the return of the Chagos islanders outside the World Court in 2018. (AP)
Protesters hold banners supporting the return of the Chagos islanders outside the World Court in 2018. (AP)

In 2019, the International Court of Justice said the 1965 separation had not been based on "free and genuine expression of the people concerned". "This continued administration constitutes a wrongful act," it added.

The agreement, which has been under negotiation since 2022 means Mauritius will gain sovereignty over the islands, but they will guarantee the presence of the UK-US naval base on Diego Garcia for 99 years, with an option to renew.

The Foreign Office said the agreement means the status of the base will be undisputed and legally secure.

The UK will pay a regular annual sum of money during the agreement and there will be funding to help benefit Chagossians.

The islands have seen several asylum seekers arrive in recent years. The deal says Mauritius would be responsible for any future arrivals under the new agreement.

A joint statement from the UK and Mauritius governments said the treaty will “address wrongs of the past and demonstrate the commitment of both parties to support the welfare of Chagossians”.

Chagossians demonstrating against their treatment by the UK government in 2016. (AP)
Chagossians demonstrating against their treatment by the UK government in 2016. (AP)

They also said the agreement will “herald a new era of economic, security and environmental partnership between our two nations”, adding: “To enable this partnership the UK will provide a package of financial support to Mauritius.

“This will include an indexed annual payment for the duration of the agreement and the establishment of a transformational infrastructure partnership, underpinned by UK grant funding, to deliver strategic projects generating meaningful change for ordinary Mauritians and boosting economic development across the country.”

US president Joe Biden welcomed the “historic” agreement and said it secures the “effective operation of the joint facility on Diego Garcia into the next century”.

The government has argued the legal dispute over the islands put the naval base at risk and by signing this deal they guarantee its future. Foreign secretary David Lammy said the deal would "strengthen our role in safeguarding global security" and "shut down any possibility of the Indian Ocean being used as a dangerous illegal migration route to the UK".

The Conservatives have reacted with anger at the deal, with all of the leadership contenders being quick to attack Labour for negotiating it. Former foreign secretary James Cleverly, who opened the negotiations under the previous administration and had aimed to complete them in 2023, said Labour had been "weak".

Cleverly wrote on social media: “Weak, weak, weak! Labour lied to get into office. Said they’d be whiter than white, said they wouldn’t put up taxes, said they’d stand up to the EU, said that they be patriotic. All lies!”

Fellow Tory leadership candidate Tom Tugendhat said: “This is a shameful retreat undermining our security and leaving our allies exposed.”

He said the Foreign Office had “negotiated against Britain’s interest” and it is “disgraceful that these negotiations started under our watch”.

Jonathan Powell, the prime minister’s special envoy for negotiations between the UK and Mauritius, dismissed the “silly” Tory criticism. Powell said the previous Tory administration managed to “lose the trust” of their Mauritian counterparts, telling BBC Radio 4’s World At One programme: “So for the people who were involved in that negotiation to start criticising the outcome, something they couldn’t achieve, is absolutely ludicrous.”