Key Facts and Data Points

  • Chagos Archipelago: 58 islands in the Indian Ocean, ~500 km south of the Maldives.
  • Diego Garcia: Largest island; hosts a joint UK‑US military base.
  • Historical Timeline:
  • 1715: France colonised Mauritius and Chagos.
  • 1814: Treaty of Paris ceded both to Britain.
  • 1965: Britain detached Chagos from Mauritius to form the British Indian Ocean Territory (BIOT), providing Mauritius a £3 million grant.
  • 1966: UK allowed the US to use BIOT for military purposes; base became operational in 1986.
  • 2019: International Court of Justice (ICJ) advisory opinion declared the detachment unlawful.
  • 2024: UK agreed to transfer sovereignty to Mauritius, securing a 99‑year lease on Diego Garcia.

Background and Context

  • The Chagos Islands were separated from Mauritius during the decolonisation process, a move later challenged as a breach of the right to self‑determination.
  • Diego Garcia’s strategic location enables power projection across the Indian Ocean, supporting operations in the Gulf War, Iraq, Afghanistan, and post‑9/11 missions.
  • The US‑UK partnership at Diego Garcia is a cornerstone of the Quad and broader Indo‑Pacific security architecture.

Significance for India / Governance / Policy

  • Strategic Balance: Retention of the base by the UK (and US) helps contain China’s maritime expansion, aligning with India’s Indo‑Pacific outlook.
  • Legal Precedent: The ICJ opinion reinforces the principle of self‑determination, influencing India’s stance on similar territorial disputes (e.g., Kashmir, Ladakh).
  • Maritime Security: The base supports anti‑piracy, anti‑terrorism, and humanitarian missions that affect Indian shipping lanes.
  • Diplomatic Relations: The agreement showcases the UK’s willingness to address colonial legacies, impacting its bilateral ties with Mauritius and, indirectly, with India.

Related Constitutional / Legal Provisions

  • International Court of Justice (ICJ) Advisory Opinion 2019 – based on the UN Charter’s emphasis on self‑determination and decolonisation.
  • UN General Assembly Resolution 1514 (1960) – Declaration on the Granting of Independence to Colonial Countries and Peoples.
  • Treaty of Paris (1814) – Historical treaty transferring sovereignty from France to Britain.

Implications for UPSC Aspirants

  • Understand the geopolitical importance of overseas bases in the Indian Ocean.
  • Analyze how international legal decisions shape bilateral agreements.
  • Relate the Chagos issue to India’s own strategic challenges and maritime policy.

Prepared for UPSC CSE – both Prelims and Mains.