Official Belligerents:
French Colonies and Protectorates
Colonies et protectorats français
Joined the war on: 3 August, 1914 - Colonies and Protectorates of the Republic of France
Kingdom of Belgium
Koninkrijk België
Royaume de Belgique
Königreich Belgien
Germany invaded Belgium on: 4 August, 1914
United Kingdom of Great Britain and Ireland
United Kingdom of Great Britain and Ireland
Declared war on German Empire: 4 August, 1914
British Colonies and Protectorates
British Colonies and Protectorates
Joined the war on: 4 August, 1914
Idrisid Emirate of Asir
الإمارة الإدريسية
Declared war at the Ottoman Empire on: May, 1915
Emirate of Nejd and Hasa
إمارة نجد والأحساء
Declared war at the Ottoman Empire on: 26 December, 1915
Kingdom of Romania
Regatul României
Declared war on German Empire: 27 August, 1916 (Again in 10 November, 1918)
Russian Provisional Government
Временное правительство России
Joined the war on: 15 March, 1917
Republic of the United States of Brazil
República dos Estados Unidos do Brasil
Declared war on German Empire: 26 October, 1917
Russian Soviet Republic
Российская Советская Республика
Declared war on German Empire: 7 November, 1917
Puppet States:
Autonomous Province of Korçë
Krahina Autonome e Korçës
Joined the war on: 10 December, 1916 - Puppet State of Republic of France
Questionable Belligerents:
Grand Duchy of Luxembourg
Groussherzogtum Lëtzebuerg
Grand-Duché de Luxembourg
Großherzogtum Luxemburg
Occupied by German Empire on: 2 August, 1914
Czechoslovak Legions
Československé legie
Československé légie
Was formed on: 5 August, 1914
Polish Legions
Legiony Polskie
Was formed on: 27 August, 1914
Portuguese Colony of Angola
Província Portuguesa da Angola
Fight agaisn't the German Empire on: October, 1914
Assyrian volunteers
ܡܠܟ
Fight agaisn't the German Empire on: November, 1914
Kingdom of Nepal
नेपाल अधिराज्य
Send troops to help the British Empire on: November, 1914
Sublime State of Iran
دولت علیّه ایران
Allied with Entente on: 17 November, 1914
Beda Sultanate
بيدا سلطنة
Fight agaisn't the Ottoman Empire on: February, 1915
Plurational State of Bolivia
Estado Plurinacional de Bolivia
Tetã Hetãvoregua Mborivia
Wuliwya Suyu
Puliwya Mamallaqta
Cut diplomatic relationships with German Empire on: 13 April, 1917
Republic of Peru
República del Perú
Piruw Ripuwlika
Piruw Suyu
Cut diplomatic relationships with German Empire on: 6 October, 1917
Oriental Republic of Uruguay
República Oriental del Uruguay
Cut diplomatic relationships with German Empire on: 7 October, 1917
Republic of Ecuador
República del Ecuador
Chawpipacha Ripuwlika
Ekuatur Nunka
Cut diplomatic relationships with German Empire on: 7 December, 1917
Principality of Monaco
Principauté de Monaco
Principatu de Mùnegu
Supposedly have joined the war on: July, 1918
Kingdom of Norway
Kongeriket Norge
Kongeriket Noreg
(No data)
Notes: Because UK and France had to much colonies during the Great War, I decided to create a separated site just for them. And Beda Sultanate don't have a flag.