BRITAIN acquired the Chagos Islands via a treaty signed after defeating Napoleon in 1814 and subsequently governed them from another British colony, Mauritius.

In 1965, Britain bought the Chagos archipelago from the now self-governing Mauritius — though it was still a colony — for a mere £660,000. The aim was to create the British Indian Ocean Territory to provide its ally the US with a military base in the region. The archipelago was then leased to the US until 2016, later extended until 2036.

As a consequence, from 1965 to 1973 the inhabitants of the Chagos archipelago were forcibly removed from their homeland and dumped in Mauritius and Seychelles. “We must surely be very tough about this ... there will be no indigenous population except the seagulls,” Baron Wright of the foreign and commonwealth office ominously declared in August 1966.

This callous disregard for the rights of the Chagossians and its tragic aftermath is the story told in The Chagos Betrayal by FlorIan Grosset.

Grosset is well placed to do so. She was born and grew up in Mauritius, where she witnessed at first hand the poverty in which the Chagossians have lived for decades after they were evicted from their idyllic home environment to the slums of Port Louis.

The Mauritians contemptuously called them “ilois” — the islanders and discrimination was the norm at all levels. Frequent death came from “mizer noir,” the black misery of starvation, suicide, disease and even miscarriage. There was no end to “sagri,” Creole for sorrow.

Grosset progresses the story in period-specific vignettes, contrasting the monochromes of exile with the colourful past and finally the black-and-white monotone of the struggle for restitution from the British government.

The book follows the Chagossian diaspora in their fight for the right to return through protests and court cases. Over 3,000 of them, the largest population outside Mauritius and the Seychelles, live marginalised in Crawley, west Sussex where the local authority has tried innumerable times to get them to leave Britain, despite the fact that they are actually British citizens.

“A very creative way of telling of a terrible and ongoing atrocity. It is impossible to explore this book and not feel the injustice and then feel that justice must be done,” comments Benjamin Zephaniah.

He’s backed by John Pilger, who urges that: “Every school, every library should have this book. Please read what was done in your name.”

Published by Myriad Editions, £16.99.