Diego Garcia

Diego Garcia is a strategically significant atoll located in the central Indian Ocean, forming part of the Chagos Archipelago. It is under the British Indian Ocean Territory (BIOT), though its sovereignty remains a subject of international dispute, particularly with Mauritius. The island is best known for hosting a major United States military base, which plays a vital role in American and allied defence operations across the Middle East, Africa, and Asia. Its geographical isolation, deep natural harbour, and central location have made Diego Garcia one of the most important military outposts in the Indian Ocean region.

Geographical Location and Features

Diego Garcia lies about 1,800 kilometres south of India, 2,200 kilometres east of the coast of Africa, and 1,600 kilometres southwest of Indonesia. It is the largest island in the Chagos Archipelago, which consists of more than 60 small coral atolls and islets scattered over a wide area of the Indian Ocean.

• Geographical Coordinates: Approximately 7° 18′ S latitude and 72° 24′ E longitude.
• Shape and Size: The island is roughly 44 kilometres in circumference, forming a horseshoe-shaped atoll enclosing a lagoon approximately 19 kilometres long and 8 kilometres wide.
• Climate: It experiences a tropical oceanic climate, with warm temperatures, high humidity, and significant rainfall throughout the year.

The atoll is characterised by white sandy beaches, coconut palms, and coral reefs, though its natural environment has been modified by military infrastructure.

Historical Background

The history of Diego Garcia is closely tied to the broader colonial expansion in the Indian Ocean region.

• Early Discovery and Naming: The island was likely discovered by Portuguese navigators in the early 16th century, with the name “Diego Garcia” possibly deriving from a Portuguese sailor or captain. It was later mapped by European explorers but remained uninhabited for centuries.
• French and British Colonial Rule: In the 18th century, the French colonised the Chagos Archipelago, incorporating it administratively into Mauritius. They established coconut plantations on several islands, including Diego Garcia, and brought enslaved African and later indentured Indian labourers to work there.
  Following the Napoleonic Wars, the British captured Mauritius and its dependencies in 1810, formalised by the Treaty of Paris (1814). The Chagos Islands thus came under British control as part of the Colony of Mauritius.
• Economic Activities: For much of the 19th and early 20th centuries, Diego Garcia functioned as a copra plantation economy, exporting dried coconut kernels used for oil production. The local population, known as the Chagossians (Ilois), descended from African slaves and Indian labourers, developed a distinct Creole culture on the island.

Creation of the British Indian Ocean Territory

In 1965, in the context of decolonisation and Cold War geopolitics, the United Kingdom separated the Chagos Archipelago from Mauritius to form the British Indian Ocean Territory (BIOT). This administrative change was part of a secret agreement between the UK and the United States, aimed at establishing a joint military base on Diego Garcia.
Mauritius protested the separation, claiming it violated its territorial integrity, as the Chagos Islands were historically part of Mauritian territory. Nevertheless, the UK retained control, citing strategic defence interests.

Establishment of the U.S. Military Base

Between 1968 and 1973, the United States and United Kingdom implemented an agreement allowing the U.S. to use Diego Garcia as a defence facility. The island’s location — almost equidistant from East Africa, the Middle East, and Southeast Asia — made it ideal for military logistics during the Cold War.

• Evacuation of Inhabitants: To facilitate the base construction, the entire Chagossian population was forcibly relocated between 1968 and 1973 to Mauritius and the Seychelles. This mass displacement remains one of the most controversial aspects of Diego Garcia’s history, with international criticism and ongoing legal disputes.
• Construction of the Base: The U.S. built extensive infrastructure, including airstrips, naval facilities, fuel storage, and communication systems. The base became operational in 1971 and expanded over subsequent decades to accommodate large aircraft such as B-52 bombers, cargo planes, and naval vessels.

Strategic and Military Importance

Diego Garcia is considered one of the most important forward-operating bases for U.S. and allied forces in the Indian Ocean.

• Geostrategic Location: Its central position allows rapid military reach to West Asia, East Africa, and Southeast Asia. The island serves as a key node for power projection, intelligence operations, and logistics in the broader Indo-Pacific region.
• Operational Role: Diego Garcia has been used extensively in major conflicts, including:
  • The Gulf War (1991), when U.S. bombers and naval forces launched operations against Iraq.
  • The Afghanistan and Iraq Wars (2001–2011), providing logistical support and refuelling capabilities.
  • Ongoing counterterrorism and maritime surveillance missions across the Indian Ocean and Arabian Sea.
• Facilities: The base includes a 3,700-metre runway, deep-water anchorage, and prepositioning ships carrying equipment for the U.S. Navy and Marine Corps. It also functions as a refuelling and supply hub for long-range air operations.

Legal and Political Dispute

The sovereignty of Diego Garcia and the Chagos Archipelago remains one of the most contentious issues in modern international law.

• Mauritius’s Claim: Mauritius asserts that the separation of the Chagos Islands in 1965 violated international decolonisation principles and that it retains sovereignty over the territory.
• International Court of Justice (ICJ) Advisory Opinion (2019): The ICJ ruled that the United Kingdom’s continued administration of the Chagos Archipelago is unlawful, stating that it should end its control “as rapidly as possible.” The United Nations General Assembly subsequently passed a resolution affirming the ICJ’s opinion and recognising Mauritian sovereignty.
• UK and U.S. Position: The United Kingdom maintains de facto control over the islands, arguing that BIOT serves vital defence purposes. The U.S. continues to operate the base under a bilateral agreement renewed periodically.

Despite international pressure, the status quo remains unchanged, though diplomatic negotiations between the UK and Mauritius are ongoing.

Environmental and Ecological Aspects

Apart from its military significance, Diego Garcia is home to a unique marine ecosystem. The island’s lagoon and surrounding coral reefs support rich biodiversity, including seabirds, sea turtles, and numerous fish species. In 2010, the UK declared the Chagos Marine Protected Area, covering over 640,000 square kilometres — one of the largest marine reserves in the world.
However, this designation has been criticised as an attempt to prevent the resettlement of the displaced Chagossians, as the reserve status restricts human habitation and economic activity. Environmental management thus intersects with ongoing human rights and sovereignty disputes.

Human Rights and Resettlement Issues

The Chagossians have consistently campaigned for the right to return to their homeland. Several court cases in the UK and international forums have challenged their displacement and sought compensation or resettlement.
While some British courts initially ruled in favour of limited resettlement, subsequent appeals overturned these decisions. The issue remains unresolved, though the Chagossians continue to advocate internationally for justice and recognition.

Strategic and Contemporary Relevance

In the twenty-first century, Diego Garcia continues to play a critical role in the U.S.–UK strategic partnership. With the growing importance of the Indo-Pacific region, it remains a key asset for power projection, maritime surveillance, and maintaining freedom of navigation in vital sea lanes.
Amid rising competition involving China’s naval presence in the Indian Ocean, the base’s importance has increased further, serving as a central component of Western security architecture in Asia and Africa.

Significance and Legacy

Diego Garcia epitomises the intersection of geopolitics, colonial legacy, and human rights in the modern era. It stands as:

• A symbol of Cold War strategy and continuing global military presence in the Indian Ocean.
• A site of legal and ethical debate over sovereignty, decolonisation, and displaced populations.
• A critical node of U.S. military logistics, sustaining regional stability and operational reach.