United Nations Trust Territories were the successors of the League of Nations mandates and came into being when the League of Nations ceased to exist in 1946. All of the trust territories were administered through the UN Trusteeship Council. The one territory not turned over was South West Africa, which South Africa insisted remain under the League of Nations Mandate. The main objection was that the trust territory guidelines required that the lands be prepared for independence and majority rule. Trust territories (and administering powers) were:

• Cameroons (Britain and France),
• Nauru (Australia),
• New Guinea (Australia),
• Trust Territory of the Pacific Islands (U.S.),
• Ruanda-Urundi (Belgium),
• Somalia (Italy), Tanganyika (Britain),
• Togoland (Britain and France), and
• Western Samoa (New Zealand).