Mandate System

A League of Nations mandate was a legal status for certain territories transferred from the control of one country to another following World War I, or the legal instruments that contained the internationally agreed-upon terms for administering the territory on behalf of the League of Nations. These were of the nature of both a treaty and a constitution, which contained minority rights clauses that provided for the rights of petition and adjudication by the International Court. The mandate system was established under Article 22 of the Covenant of the League of Nations, entered into on 28 June 1919. With the dissolution of the League of Nations after World War II, it was stipulated at the Yalta Conference that the remaining Mandates should be placed under the trusteeship of the United Nations, subject to future discussions and formal agreements. Most of the remaining mandates of the League of Nations (with the exception of South-West Africa) thus eventually became United Nations Trust Territories.

Two governing principles formed the core of the Mandate System, being non-annexation of the territory and its administration as a “sacred trust of civilisation” to develop the territory for the benefit of its native people.

The mandate system was established by Article 22 of the Covenant of the League of Nations, drafted by the victors of World War I. The article referred to territories which after the war were no longer ruled by their previous sovereign, but their peoples were not considered "able to stand by themselves under the strenuous conditions of the modern world". The article called for such people's tutelage to be "entrusted to advanced nations who by reason of their resources, their experience or their geographical position can best undertake this responsibility".

All of the territories subject to League of Nations mandates were previously controlled by states defeated in World War I, principally Imperial Germany and the Ottoman Empire. The mandates were fundamentally different from the protectorates in that the Mandatory power undertook obligations to the inhabitants of the territory and to the League of Nations.

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