The acquisition and loss of state territory under international law are governed by well-established principles and rules that outline the circumstances under which territory can be acquired or ceded. These principles are essential for understanding how states acquire and relinquish control over land and other territorial features.
Acquisition of State Territory
- Treaties and Agreements: States can acquire territory through negotiated treaties and agreements with other states. These treaties, known as boundary treaties or land cession agreements, define the terms and conditions of the transfer of territory.
- Discovery and Effective Occupation: Historically, states claimed territory through discovery and effective occupation. Under this principle, a state could establish sovereignty over previously unclaimed or uninhabited land by physically occupying and administering it.
- Accretion: Accretion is the gradual buildup of land through natural processes, such as the deposition of sediment along a riverbank or coastline. States may acquire territory through accretion if it occurs within their recognized boundaries.
- Prescription: Prescription is a legal concept that allows a state to acquire territory through long-term and continuous exercise of sovereignty, even without the consent of the original sovereign. This principle is less commonly applied today.
- Annexation: Annexation occurs when one state unilaterally incorporates the territory of another state. Annexations are generally illegal under international law unless they are conducted in accordance with recognized legal principles, such as self-determination.
Loss of State Territory
- Treaties and Agreements: Just as treaties can be used to acquire territory, they can also be used to cede or transfer territory to another state. States may voluntarily cede territory through negotiated agreements.
- Secession: Secession is the process by which part of a state’s territory breaks away to form a new state. The legitimacy of secession is a complex and contentious issue in international law and often depends on factors such as the consent of the affected population, human rights considerations, and international recognition.
- Occupation by Another State: If a foreign state occupies another state’s territory through aggression or invasion, the international community typically does not recognize the occupying state’s sovereignty over that territory. The principle of non-recognition of territorial acquisitions through force (jus cogens norm) reinforces this position.
- Dismemberment and Dissolution: In cases of state dissolution or dismemberment (e.g., the breakup of the Soviet Union or Yugoslavia), the newly independent entities may be recognized as separate states and may inherit portions of the former state’s territory.
- Territorial Adjustment: States may agree to adjust their boundaries through treaties or negotiations. Such adjustments can lead to the transfer of territory from one state to another, provided that both parties consent.
- International Court Decisions: In some cases, international courts or tribunals may decide boundary disputes or territorial claims, leading to adjustments in state territory based on legal principles and evidence presented during the proceedings.
