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 and their colonies
|
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/Canada/Australia/and the remainder of the
British Common Wealth and Empire including India.
|
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
United States
|
Declared war on Germany
....April 6, 1917
|
Declared war on Austria-Hungary
....Dec 7, 1917
Uruguay
|
Severed relations with Germany
.....Oct 7, 1917
|