Modes of Acquisition and Loss of State Territory

Territory is an essential element of statehood under international law. The acquisition and loss of territory by states follow specific legal principles that ensure legitimacy and respect for sovereignty.

1. Modes of Acquisition of State Territory

Traditionally, the following modes are recognized under public international law for lawful acquisition of territory:

• Occupation: Acquisition of terra nullius (land belonging to no one) through effective control and intention to act as sovereign. Example: Island claims in the Pacific.
• Accretion: Natural, gradual addition of land through geological processes such as river deposits or volcanic activity. Example: Delta formation extending coastal lines.
• Cession: Transfer of territory from one state to another by treaty or agreement. Example: Louisiana Purchase (1803), India-Bangladesh land boundary agreement (2015).
• Conquest (Obsolete): Historically, acquisition by force was practiced, but it is now prohibited under the UN Charter. Modern international law does not recognize acquisition through armed aggression.
• Prescription: Peaceful, continuous, and public exercise of sovereignty over a territory for a prolonged period without protest from the original sovereign.
• Adjudication: Acquisition through decision of an international tribunal or court resolving a territorial dispute. Example: ICJ judgment in the Burkina Faso–Niger border dispute (2013).

2. Modes of Loss of State Territory

A state may lose territory under the following circumstances:

• Cession: Voluntary transfer of territory by treaty. Example: Transfer of Hong Kong from the UK to China in 1997.
• Dereliction: Voluntary abandonment of territory by the sovereign state, allowing it to become terra nullius.
• Submergence: Physical loss of territory due to natural causes like rising sea levels or erosion (increasingly relevant under climate change).
• Conquest (Invalid Today): Historically valid but currently prohibited and not recognized as a lawful means of loss.
• Revolution or Secession: A part of a state breaking away and gaining recognized independence or being absorbed by another state. Example: Dissolution of the USSR (1991).

3. Legal and Political Considerations

All territorial changes must comply with international law, especially principles of:

• Non-use of force (UN Charter Article 2(4))
• Respect for self-determination of peoples
• Peaceful settlement of disputes

4. Conclusion

The acquisition and loss of state territory are subject to both historical practice and evolving legal norms. International law emphasizes peaceful methods, legitimacy, and respect for sovereign rights in all territorial matters.

---

Published by Pavan Law Chambers | Public International Law Series