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. 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.