Declarations of War.

The Nations Involved in the Great War

(from the Funk & Wagnalls New Encyclopaedia, 1983, Volume 27, p 418)

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Austria-Hungary
Declared war on Serbia .........July 28, 1914
Declared war on Russia ........Aug 6, 1914
Declared war on Belgium ......Aug 28, 1914
Declared war on Portugal ......March 15, 1916

Belgium
Refused German ultimatum demanding permission for German troops to cross Belgium Aug 2, 1914
Invaded by Germany .........Aug 3-4, 1914

Bolivia
Severed relations with Germany ........April 13, 1917

Brazil
Severed relations with Germany .....April 11, 1917
Declared war on Germany .......Oct 26, 1917

Bulgaria
Declared war on Serbia .......Oct 14, 1915
Declared war on Romania ......Sept 1, 1916

China
Severed relations with German .....March 14, 1917
Declared war on Germany .....Aug 14, 1917
Declared war on Austria-Hungary ....Aug 14, 1917

Costa Rica
Severed relations with Germany ....Sept 21, 1917
Declared war on Germany ...May 23, 1918

Cuba
Declared war on Germany ....April 7, 1917

Ecuador
Severed relations with Germany ....Dec 8, 1917

France
Invaded by Germany ......Aug 2, 1914
Declared war on Austria-Hungary .....Aug 12, 1914
Declared war on Turkey ....Nov 5, 1914
Declared war on Bulgaria ....Oct 16, 1915

Germany
Declared war on Russia ....Aug 1, 1914
Declared war on France ....Aug 3, 1914
Declared war on Belgium ....Aug 4, 1914
Declared war on Portugal .....March 9, 1916

Great Britain
Declared war on Germany ....Aug 4, 1914
Declared war on Austria-Hungary ....Aug 12, 1914
Declared war on Turkey ....Nov 5, 1914
Declared war on Bulgaria ....Oct 15, 1915

Greece
Declared war on Austria-Hungary, Bulgaria, Germany and Turkey ....June 27, 1917

Guatemala
Declared war on Germany ....April 23, 1918

Haiti
Declared war on Germany ....July 12, 1918

Honduras
Declared war on Germany ....July 19, 1918

Italy
Declared war on Austria-Hungary .....May 23, 1915
Declared war on Turkey .....Aug 21, 1915
Declared war on Bulgaria .....Oct 19, 1915
Declared war on Germany ......Aug 28, 1916

Japan

Declared war on Germany .....Aug 23, 1914

Declared war on Austria-Hungary .....Aug 25, 1914

Liberia

Declared war on Germany .....Aug 4, 1914

Montenegro

Declared war on Austria-Hungary ....Aug 5, 1914

Declared war on Germany .....Aug 8, 1914

Declared war on Bulgaria .....Oct 15, 1915

Nicaragua

Declared war on Germany and Austria-Hungary .....May 8, 1918

Panama

Declared war on Germany ....April 7, 1917

Declared war on Austria-Hungary .....Dec 10, 1917

Peru

Severed relations with Germany .....Oct 6, 1917

Portugal

See Germany and Austria-Hungary in this table

Romania

Declared war on Austria-Hungary ....Aug 27, 1916

Capitulated to Central Powers by Treaty of Bucharest .....May 7, 1918

Re-entered the war on the side of the Allies ....Nov 10, 1918

Russia

Declared war on Turkey .....Nov 2, 1914

Declared war on Bulgaria ....Oct 19, 1915

San Marino

Declared war on Austria-Hungary ....June 3, 1915

Serbia

Declared war on Germany .....Aug 6, 1914

Declared war on Turkey .....Nov 2, 1914

Siam

Declared war on Germany and Austria-Hungary .....July 22, 1917

Turkey

Declared war on Romania ....Aug 30, 1916

Severed relations with the US .....April 23, 1917

US

Declared war on Germany ....April 6, 1917

Declared war on Austria-Hungary ....Dec 7, 1917

Uruguay

Severed relations with Germany .....Oct 7, 1917

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