Sovereign States

A

• Afghanistan – Emirate of Afghanistan (from August 19)
• Albania – Principality of Albania
•  Andorra – Principality of Andorra
•  Argentina – Argentine Republic
• Armenia – Democratic Republic of Armenia
• Asir – Emirate of Asir
• Upper Asir – Emirate of Upper Asir
•  Australia – Commonwealth of Australia
•  Austria – Republic of Austria (from September 10)
• Azerbaijan – Azerbaijan Democratic Republic

B

•  Belgium – Kingdom of Belgium
•  Bolivia – Republic of Bolivia
•  Brazil – Republic of the United States of Brazil
• Bulgaria – Kingdom of Bulgaria

C

•  Canada – Dominion of Canada
•  Chile – Republic of Chile
•  China – Republic of China
•  Colombia – Republic of Colombia
•  Costa Rica – Republic of Costa Rica
•  Cuba – Republic of Cuba
• Czechoslovakia – Czecho-Slovak Republic

D

•  Denmark – Kingdom of Denmark
•  Dominican Republic – Dominican Republic

E

•  Ecuador – Republic of Ecuador
•  El Salvador – Republic of El Salvador
•  Estonia – Republic of Estonia
• Ethiopia – Empire of Ethiopia

F

• Finland
  • Kingdom of Finland (to July 17)
  • Republic of Finland (from July 17)
• France – French Republic

G

• Georgia – Democratic Republic of Georgia
• German Austria – Republic of German Austria (to September 10)
•  Germany – German Reich
• Greece – Kingdom of Greece
•  Guatemala – Republic of Guatemala

H

• Ha'il – Emirate of Ha'il
•  Haiti – Republic of Haiti
•  Hejaz – Kingdom of Hejaz
•  Honduras – Republic of Honduras
• Hungary – Hungarian Democratic Republic (to March 21)

I

• Iceland – Kingdom of Iceland
• Italy – Kingdom of Italy

J

•  Japan – Empire of Japan

L

•  Latvia – Republic of Latvia
  • Latvian Socialist Soviet Republic
•  Liberia – Republic of Liberia
• Liechtenstein – Principality of Liechtenstein
•  Lithuania – Republic of Lithuania
•  Luxembourg – Grand Duchy of Luxembourg

M

•  Mexico – United Mexican States
•  Monaco – Principality of Monaco

N

• Nejd – Emirate of Nejd
•  Netherlands – Kingdom of The Netherlands
•  Newfoundland – Dominion of Newfoundland
• New Zealand – Dominion of New Zealand
•  Nicaragua – Republic of Nicaragua
•  Norway – Kingdom of Norway

O

•  Ottoman Empire – Sublime Ottoman State

P

•  Panama – Republic of Panama
• Paraguay – Republic of Paraguay
• Persia – Persian Empire
•  Peru – Peruvian Republic
• Poland – Republic of Poland
•  Portugal – Portuguese Republic

R

• Romania – Kingdom of Romania
• Russia – Russian Soviet Federative Socialist Republic

S

•  San Marino – Most Serene Republic of San Marino
•  Serbs, Croats and Slovenes – Kingdom of Serbs, Croats, and Slovenes
•  Siam – Kingdom of Siam
• South Africa – Union of South Africa
• Spain – Kingdom of Spain
•  Sweden – Kingdom of Sweden
•  Switzerland – Swiss Confederation

U

• United Kingdom – United Kingdom of Great Britain and Ireland
•  United States – United States of America
•  Uruguay – Eastern Republic of Uruguay

V

•  Venezuela – United States of Venezuela

Y

• Yemen – Mutawakkilite Kingdom of Yemen

States Claiming Sovereignty

• Alash – Alash Autonomy
• Bavaria – Bavarian Soviet Republic (from April 6 to May 3)
• Belarus – Belarusian People's Republic (renamed Byelorussia on January 5)
• Bessarabia – Bessarabian Soviet Socialist Republic (from May 5 to September)
•  Bottleneck – Free State Bottleneck (from January 12)
• Byelorussia – Byelorussian Soviet Socialist Republic (from January 5 to February 27)
• Carnaro – Italian Regency of Carnaro (from September 12)
• Don – Don Republic
• Estonia – Commune of the Working People of Estonia (to June 5)
• Hungary – Hungarian Soviet Republic (from March 21 to August 6)
• Ireland – Irish Republic (from January 21)
• Kars – Democratic Republic of South West Caucasus (to April 19)
• Komancza – Komancza Republic (to January 23)
•  Kuban – Kuban People's Republic
• Lado – Lado District
• Lemko-Rusyn – Lemko-Rusyn Republic
• Litbel – Lithuanian-Belorussian Soviet Socialist Republic (from February 27 to August 25)
• Mughan – Mughan Soviet Republic (from March to June)
• North Caucasian Emirate – North Caucasian Emirate
• Northern Caucasus – Mountainous Republic of the Northern Caucasus
• Prekmurje – Republic of Prekmurje (from May 29 to June 6)
• Slovakia – Slovak Soviet Republic (from June 16 to July 7)
• Tavolara – Kingdom of Tavolara
•  Tibet – Tibet
• Ukraine – Ukrainian People's Republic (to February)
  • Ukrainian Soviet Socialist Republic
• West Ukraine – West Ukrainian National Republic (to January 22)
• White Russia – Provisional All-Russian Government (to January)