List of state leaders in the 20th century (1901–1950)

Africa

Africa: Central

• Kingdom of Kongo –
• Portuguese Angola, –

• Kamerun –
• French Cameroons, part of French Equatorial Africa –
• British Cameroons part of British West Africa –

• Ubangi-Shari part of French Equatorial Africa –

• Sultanate of Bagirmi –
• Wadai Empire –
• French Chad, part of French Equatorial Africa –

• Congo Free State
• Belgian Congo –

• French Congo part of French Equatorial Africa –
• French Equatorial Africa –

• Spanish Guinea –

• Kingdom of Orungu –
• French Gabon, part of French Equatorial Africa –

• Portuguese São Tomé and Príncipe –

  Africa: East

• Kingdom of Burundi –
• Ruanda-Urundi –
• Wituland –
• East Africa Protectorate –
• Kenya Colony –
• Kingdom of Rwanda –
• Sultanate of Zanzibar –
• German East Africa –
• Tanganyika under Britain –
• Ankole –
• Buganda –
• Bunyoro –
• Uganda Protectorate –

• French Somaliland –
• Italian Eritrea –
• Ethiopian Empire –
• Italian East Africa –
• Sultanate of Aussa –
• Kingdom of Gumma –
• Kingdom of Jimma –
• Sultanate of Hobyo –
• Majeerteen Sultanate –
• Italian Somaliland part of Italian East Africa –
• British Somaliland –
• Trust Territory of Somaliland –

• Sultanate of Mwali –
• Sultanate of Ndzuwani –
• French Comoros –
• French Madagascar –
• British Mauritius –
• Colony of Seychelles

  Africa: Northcentral

• Italian Libya –
• Allied administration of Libya –
• Cyrenaica Emirate –

• Beylik of Tunis
• French protectorate of Tunisia –

  Africa: Northeast

• Khedivate of Egypt
• Sultanate of Egypt
• Kingdom of Egypt

• Sultanate of Darfur –
• Anglo-Egyptian Sudan –

  Africa: Northwest

• French Algeria –

• Morocco: Alaouite dynasty –
• Spanish Sahara, –

  Africa: South

• Bechuanaland Protectorate –

• Basutoland –

• British Central Africa Protectorate –
• Nyasaland –

• Portuguese Mozambique –

• German South West Africa –
• South West Africa –

• British Central Africa Protectorate –
• Cape Colony –
• Colony of Natal –
• Orange Free State –
• Orange River Colony –
• South African Republic –
• Transvaal Colony –
• Union of South Africa

• Swaziland

• Kazembe –
• Barotseland –
• Company rule in Rhodesia by the British South Africa Company –
• Northern Rhodesia –

• Southern Rhodesia –

  Africa: West

• Dahomey –
• French Dahomey, part of French West Africa –

• Mossi Kingdom of Bilayanga –
• Mossi Kingdom of Bongandini –
• Mossi Kingdom of Con –
• Mossi Kingdom of Gwiriko –
• Mossi Kingdom of Kuala –
• Mossi Kingdom of Liptako –
• Mossi Kingdom of Macakoali –
• Mossi Kingdom of Nungu –
• Mossi Kingdom of Pama –
• Mossi Kingdom of Piéla –
• Mossi Kingdom of Tenkodogo –
• Mossi Kingdom of Wogodogo –
• Mossi Kingdom of Yatenga –
• French Upper Volta part of French West Africa –

• Portuguese Cape Verde –

• Gambia Colony and Protectorate –

• Kingdom of Ashanti –
• Gold Coast –

• French Guinea part of French West Africa –

• Portuguese Guinea –

• French Ivory Coast part of French West Africa –

• Liberia –

• French Sudan part of French West Africa –

• Colonial Mauritania part of French West Africa –

• Dendi Kingdom –
• Upper Senegal and Niger part of French West Africa –
• Colony of Niger part of French West Africa –

• Akwa Akpa –
• Kano Emirate
• Kingdom of Nri –
• Sokoto Caliphate
• Yauri Emirate –
• Lagos Colony –
• Northern Nigeria Protectorate –
• Southern Nigeria Protectorate –
• Colonial Nigeria –

• Kingdom of Sine –
• Saloum –
• Senegambia and Niger part of French West Africa –
• Upper Senegal and Niger part of French West Africa –
• French Senegal part of French West Africa –
• French West Africa –

• Sierra Leone Colony and Protectorate, British colony –

• German Togoland, German protectorate –
• British Togoland –
• French Togoland –

  Americas

Americas: Caribbean

• Cuba
• Dominican Republic –
• Haiti

  Americas: Central

• Costa Rica –

• El Salvador –

• Guatemala –

• Honduras –

• Nicaragua –

• Panama –

  Americas: North

• Canada
• Mexico –
• United States –

  Americas: South

• Argentina –

• Bolivia –

• First Brazilian Republic –
• Vargas Era Brazil –
• Second Brazilian Republic –

• Chile –

• Colombia –

• Ecuador –

• Paraguay –

• Peru –

• Uruguay –

• Venezuela –

  Asia

Asia: Central

• Khanate of Khiva –
• Khorezm People's Soviet Republic
• Emirate of Bukhara –
• Bukharan People's Soviet Republic
• Russian Turkestan –

• Tibet under Qing rule –
• Tibet –

  Asia: East

• Qing dynasty –

• Republic of China
• Empire of China
• Republic of China
• Republic of China: Taiwan
• People's Republic of China

• Empire of Japan
• State of Japan

• Korean Empire –
• Japanese Korea, –
• North Korea: Democratic People's Republic of Korea
• South Korea: Republic of Korea

• Bogd Khaganate
• Mongolian People's Republic

  Asia: Southeast

• Protectorate of Brunei –

• French Protectorate of Cambodia

• Sumenep –
• Surakarta Sunanate –
• Yogyakarta Sultanate –
• Mangkunegaran –
• Pakualaman –
• Aceh Sultanate –
• Sultanate of Deli –
• Sultanate of Langkat –
• Sultanate of Siak Sri Indrapura –
• Sultanate of Serdang –
• Riau-Lingga Sultanate –
• Jambi Sultanate –
• :Thaha Safiuddin, Sultan
• Sultanate of Sambas –
• Sultanate of Bulungan –
• Pontianak Sultanate –
• Sultanate of Gowa –
• Luwu –
• Kingdom of Larantuka –
• Bima Sultanate –
• Amanatun –
• Amarasi –
• Amabi –
• Sonbai Besar –
• Sonbai Kecil –
• Amanuban –
• Sultanate of Bacan –
• Sultanate of Tidore –
• Sultanate of Ternate –
• State of East Indonesia
• Republic of Indonesia / United States of Indonesia

• Kingdom of Champasak –
• French Protectorate of Luang Phrabang –
• Kingdom of Laos

• Kedah Sultanate –
• Kelantan Sultanate: Patani dynasty –
• Perak Sultanate: Siak dynasty –
• Terengganu Sultanate –
• Selangor Sultanate –
• Negeri Sembilan –
• Perlis –
• Federated Malay States –
• Unfederated Malay States –
• Straits Settlements –
• Malayan Union –
• Kingdom of Sarawak –
• Crown Colony of Sarawak –
• Crown Colony of Labuan –
• North Borneo/Crown Colony –

• British Burma, part of the British Raj –
• Union of Burma

• Sultanate of Sulu –
• Sultanate of Maguindanao –
• Spanish East Indies, part of the Captaincy General of the Philippines –
• Tagalog Republic –
• First Philippine Republic
• Insular Government of the Philippine Islands –
• Philippines

• Colony of Singapore –

• Siam/Thailand: Rattanakosin Kingdom –

• Portuguese Timor –

• Nguyễn dynasty –
• French Indochina –
• Democratic Republic of Vietnam
• State of Vietnam

  Asia: South

• Emirate of Afghanistan: Barakzai dynasty –

• Kingdom of Afghanistan

• Nawabs of Murshidabad –
• Mallabhum –

• Bhutan

• British Raj
• Dominion of India
• Republic of India

• Sultanate of the Maldives: Huraa Dynasty –

• Kingdom of Nepal

• Dominion of Pakistan

• British Ceylon –
• Dominion of Ceylon

  Asia: West

• Bahrain –

• British Cyprus –

• Sublime State of Persia
• Imperial State of Iran

• Mandatory Iraq: Kingdom of Iraq under British Administration
• Kingdom of Iraq

• Israel

• Emirate of Transjordan
• Kingdom of Jordan

• Sheikhdom of Kuwait –

• Lebanon

• Oman –

• Qatar –

• Emirate of Jabal Shammar –
• Kingdom of Hejaz –
• Emirate of Nejd and Hasa –
• Sultanate of Nejd –
• Kingdom of Hejaz and Nejd –
• Saudi Arabia –

• Arab Kingdom of Syria
• Syrian Republic

• Ottoman Empire
• Ankara Government of Turkey
• Republic of Turkey

• Emirate of Abu Dhabi –
• Emirate of Dubai –
• Emirate of Sharjah –
• Emirate of Ajman –
• Umm Al Quwain –
• Emirate of Fujairah –
• Emirate of Ras Al Khaimah –

• Mutawakkilite Kingdom of Yemen

• Kathiri State of Seiyun –
• Lower Yafa –
• Upper Yafa –
• Sultanate of Lahej –
• Mahra Sultanate –
• Colony of Aden –

  Europe

Europe: Balkans

• Independent Albania / Provisional Government
• Principality of Albania
• Albanian Republic –
• Albanian Kingdom
• Italian occupied Albania
• German occupied Albania
• People's Socialist Republic of Albania

• Principality of Bulgaria
• Kingdom of Bulgaria
• People's Republic of Bulgaria

• Kingdom of Greece
• Second Hellenic Republic
• Kingdom of Greece: 4th of August Regime

• Kingdom of Serbia / Kingdom of Serbs, Croats and Slovenes / Kingdom of Yugoslavia
• Socialist Federal Republic of Yugoslavia
• Principality of Montenegro
• Kingdom of Montenegro

  Europe: British Isles

• Irish Free State
• Republic of Ireland

• United Kingdom of Great Britain and Ireland
• United Kingdom of Great Britain and Northern Ireland

  Europe: Central

• Austria-Hungary: Austrian Empire and Kingdom of Hungary
• Republic of German-Austria
• First Austrian Republic
• Republic of Austria

• Kingdom of Bohemia –
• Czechoslovakia: First Republic
• Czechoslovakia: Second Republic
• German occupation of Czechoslovakia
• First Slovak Republic, Nazi client state
• Czechoslovakia: Third Republic
• Czechoslovak Socialist Republic

• Kingdom of Bavaria –

• Kingdom of Prussia –

• Principality of Waldeck and Pyrmont –

• Kingdom of Saxony –
• Duchy of Brunswick –
• Free City of Lübeck –

• Duchy of Anhalt –
• Saxe-Altenburg/Saxe-Hildburghausen –
• Saxe-Meiningen –
• Saxe-Weimar-Eisenach –
• Saxe-Coburg and Gotha –

• Grand Duchy of Baden –
• Weingarten Abbey –
• Kingdom of Württemberg –

• German Empire
• Weimar Republic of Germany
• Nazi Germany
• East Germany
• West Germany

• First Hungarian Republic
• Hungarian Soviet Republic
• Hungarian Republic
• Kingdom of Hungary
• Second Hungarian Republic
• Hungarian People's Republic

• Liechtenstein

• Second Polish Republic
• People's Republic of Poland

• Switzerland –

  Europe: East

• Estonian Provisional Government
• Republic of Estonia
• Republic of Latvia
• Republic of Lithuania

• Moldavian Democratic Republic
• Kingdom of Romania
• Socialist Republic of Romania
• Russian Empire
• Russian Republic
• Russian Soviet Federative Socialist Republic, Sovereign state
• Soviet Union
• Ukrainian People's Republic
• West Ukrainian People's Republic –

  Europe: Nordic

• Denmark

• Kingdom of Finland
• Republic of Finland

• Kingdom of Iceland
• Republic of Iceland

• Norway

• Union between Sweden and Norway

• Sweden

  Europe: Southcentral

• Kingdom of Italy
• Republic of Italy

• San Marino

• Vatican City

  Europe: Southwest

• Andorra

• Kingdom of Portugal
• First Portuguese Republic
• Second Portuguese Republic

• Bourbon Restoration of Spain
• Second Spanish Republic
• Francoist Spain

  Europe: West

• Belgium

• French Third Republic
• Vichy France
• Provisional Government of the French Republic
• French Fourth Republic

• Grand Duchy of Luxembourg

• Monaco

• Kingdom of the Netherlands

  Eurasia: Caucasus

• First Republic of Armenia

• Azerbaijan Democratic Republic

• Democratic Republic of Georgia

  Oceania

• Australia

• Dominion of New Zealand
• New Zealand

• Kingdom of Tonga