1917 state leaders - Events of 1918 - 1919 state leaders - State leaders by year

Africa

• Ethiopia - Zauditu, Emperor of Ethiopia (1916-1930)
• Liberia - Daniel E. Howard, President of Liberia (1912-1920)
• South Africa
  • Monarch - King George V, King of South Africa (1910-1936)
  • Governor-General - Viscount Buxton, Governor-General of South Africa (1914-1920)
  • Prime Minister - Louis Botha, Prime Minister of South Africa (1910-1919)
• Zanzibar - Sayyid Khalifa bin Harub Al-Busaid, Sultan of Zanzibar (1911-1960)

Asia

• Afghanistan - Habibullah Khan, King of Afghanistan (1901-1919)
• Brunei - Muhammad Jamalul Alam II, Sultan of Brunei (1906–1924)
• China
  • President -
    1. Feng Kuo-Chang, President of the Republic of China (1917-1918)
    2. Hsu Shih-Chang, President of the Republic of China (1918-1922)
  • Premier -
    1. Weng Shizhen , Acting Premier of the Republic of China (1917-1918)
    2. Duan Qirui, Premier of the Republic of China (1918)
    3. Qian Nengxun , Premier of the Republic of China (1918-1919)
• Japan
  • Monarch - Taisho Emperor, Emperor of Japan (1912-1926)
  • Prime Minister -
    1. Terauchi Masatake, Prime Minister of Japan (1916-1918)
    2. Hara Takashi, Prime Minister of Japan (1918-1921)
• Oman - Taimur Bin Faisal, Sultan of Oman (1913-1932)

Australia and Oceania

• Australia -
  • Monarch - George V, King of the United Kingdom (1910-1936)
  • Governor-General - Ronald Munro-Ferguson, Governor-General of Australia (1914-1920)
  • Prime Minister - Billy Hughes, Prime Minister of Australia (1915-1923)

Europe

• Albania -
  1. National government collapsed (1916-1918)
  2. Turhan Pashë Permeti , Chairman of the Provisional Government (1918-1920)
• Denmark
  • Monarch - Christian X, King of Denmark (1912-1947)
  • Prime Minister - Carl Theodor Zahle, Prime Minister of Denmark (1913-1920)
• Finland -
  • Monarch - Väinö I of Finland, King of Finland (1918) Renounced throne
  • Regent -
    1. Pehr Evind Svinhufvud (May 1918-December 1918)
    2. Carl Gustaf Emil Mannerheim (December 1918-1919)
  • Prime Minister -
    1. Pehr Evind Svinhufvud, Prime Minister of Finland (1917-1918)
    2. Juho Kusti Paasikivi, Prime Minister of Finland (1918)
    3. Lauri Ingman, Prime Minister of Finland (1918-1919)
• France -
  • President - Raymond Poincaré, President of France (1913-1920)
  • Prime Minister - Georges Clemenceau, President of the Council (1917-1920)
• Germany -
  • Head of State -
    1. Wilhelm II, German Emperor (1888-1918)
    2. Executive Council of the Workers and Soldiers' Councils of Greater Berlin (1918)
    3. Central Council of the German Socialist Republic (1918-1919)
  • Chancellor -
    1. Georg von Hertling, Chancellor of Germany (1917-1918)
    2. Prince Maximilian of Baden, Chancellor of Germany (1918)
    3. Friedrich Ebert, Chancellor of Germany (1918)
    4. Friedrich Ebert and Hugo Haase , Chairmen of the Council of People's Commissioners (1918)
    5. Friedrich Ebert, Chairman of the Council of People's Commissioners (1918)
    6. Friedrich Ebert and Philipp Scheidemann, Chairmen of the Council of People's Commissioners (1918)
    7. Friedrich Ebert, Executive Chairman of the Council of People's Commissioners (1918-1919)
• Italy
  • Monarch - Vittorio Emanuele III, King of Italy (1900-1946)
  • Prime Minister - Vittorio Orlando, Prime Minister of Italy (1917-1919)
• Romania - King Ferdinand (1914-1927)
  1. Ion I.C. Brătianu , Prime Minister of Romania (1914-1918)
  2. Alexandru Averescu, Prime Minister of Romania (1918)
  3. Alexandru Marghiloman, Prime Minister of Romania (1918)
  4. Constantin Coandă , Prime Minister of Romania (1918)
  5. Ion I.C. Brătianu , Prime Minister of Romania (1918-1919)
• United Kingdom -
  • Monarch - George V, King of the United Kingdom (1910-1936)
  • Prime Minister - David Lloyd George, Prime Minister of the United Kingdom (1916-1922)

North America and the Caribbean

• Canada
  • Monarch - King George V, King of Canada (1910-1936)
  • Governor-General - Duke of Devonshire, Governor-General of Canada (1916-1921)
  • Prime Minister - Sir Robert Borden, Prime Minister of Canada (1911-1920)
• Haiti
  1. Philippe Sudré Dartinguenave - President of Haiti (1915-1922)
• Newfoundland
  • Monarch - King George V, King of Newfoundland {1910-1936}
  • Governor - Charles A. Harris , Governor of Newfoundland (1917-1922)
  • Prime Minister - William F. Lloyd, Prime Minister of Newfoundland (1918-1919)
• United States - Woodrow Wilson, President of the United States (1913-1921)

South America

• Brazil -
  1. Venceslau Brás Pereira Gomes, President of Brazil (1914-1918)
  2. Delfim Moreira, Acting President of Brazil (1918-1919)
• Paraguay - Manuel Franco , President of Paraguay (1916-1919)
• Peru - José Pardo y Barreda , President of Peru (1915-1919)