View source for Social:Declarations of war during World War I

A [[Social:Declaration of war|declaration of war]] is a formal act by which one nation goes to war against another.  A declaration is usually an act of delivering a performative speech (not to be confused with a mere ''speech'') or the presentation of a signed document by an authorized party of a national government in order to create a [[Social:War|state of war]] between two or more sovereign states. In the context of [[Social:World War I|World War I]], the official international protocol for declaring war was defined in the Hague Convention of 1907 (or Hague II).<ref>[http://avalon.law.yale.edu/20th_century/hague03.asp ''On the Opening of Hostilities'']; 1907; Yale Law School Library; retrieved March 2014.</ref> For the diplomatic maneuvering behind these events, which led to hostilities between nations, see Diplomatic history of World War I.
==List of war declarations==
Below is a table showing the outbreaks of wars between nations which occurred during World War I. Indicated are the dates (during the immediate build-up to, or during the course of, World War I) from which a ''de facto'' [[Social:War|state of war]] existed between nations. The table shows both the initiator states and the state at which the declaration of war was aimed. Events listed include those in which there were a simple diplomatic breaking of relations that did not involve any physical attack, as well as those involving overt declarations or acts of aggression. 
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{| class="wikitable sortable" 
!Date<ref>{{cite web |url=https://www.loc.gov/law/help/digitized-books/world-war-i-declarations/foreign.php#U |title=World War: Declarations of War from Around the World|last=|first= |date=|website=|publisher=Library of Congress|access-date=|quote= }}</ref><ref>{{cite web |url=http://www.firstworldwar.com/features/declarationsofwar.htm |title=Who Declared War and When|last=|first= |date=|website=|publisher = Firstworldwar.com|access-date=|quote= }}</ref><ref name="Becket">Ian F.W. Becket, [http://books.google.ro/books?id=CMYbKgcAW88C&printsec=frontcover&dq=The+Great+War&hl=ro&sa=X&ei=1AMAVIO6KsnnaMreguAN&ved=0CC8Q6AEwAg#v=onepage&q=Romania&f=false The Great War], second edition, Pearson Education Ltd., 2007, {{ISBN|978-1-4058-1252-8}}</ref>
!Initiator states!!Targeted states
|-
|July 28, 1914
|{{flagcountry|Austria-Hungary}}
|{{flagcountry|Kingdom of Serbia}}
|-

|-
|August 1, 1914
| rowspan="3" |{{flagcountry|German Empire}}
|{{flagcountry|Russian Empire}}
|-
| rowspan="2" |August 3, 1914
||{{flagcountry|Belgium}}
|-
||{{flagcountry|France|1794}}
|-
|August 4, 1914
|{{flagcountry|British Empire}}
|{{flagcountry|German Empire}}
|-
|August 5, 1914
|{{flagcountry|Kingdom of Montenegro}}
|{{flagcountry|Austria-Hungary}}
|-
| rowspan="2" |August 6, 1914
|{{flagcountry|Austria-Hungary}}
|{{flagcountry|Russian Empire}}
|-
|{{flagcountry|Kingdom of Serbia}}
| rowspan="2" |{{flagcountry|German Empire}}
|-
|August 8, 1914
|{{flagcountry|Kingdom of Montenegro}}
|-
|rowspan="2"|August 12, 1914
|{{flagcountry|British Empire}}
|rowspan="2"|{{flagcountry|Austria-Hungary}}
|-
|{{flagcountry|France|1794}}
|-
|August 23, 1914
| rowspan="2" |{{flagcountry|Empire of Japan}}
|{{flagcountry|German Empire}}
|-
|August 25, 1914
|{{flagcountry|Austria-Hungary}}
|-
|August 28, 1914
|{{flagcountry|Austria-Hungary}}
|{{flagcountry|Belgium}}
|-
|November 1, 1914
|{{flagcountry|Russian Empire}}
| rowspan="3" |{{flagcountry|Ottoman Empire}}
|-
| rowspan="2" |November 5, 1914
|{{flagcountry|France|1794}}
|-
|{{flagcountry|British Empire}}
|-
| rowspan="3" |November 11, 1914
| rowspan="3" |{{flagcountry|Ottoman Empire}}
|{{flagcountry|Russian Empire}}
|-
|{{flagcountry|Empire of Japan}}
|-
|{{flagcountry|British Empire}}
|-
|December 2, 1914
|{{flagcountry|Kingdom of Serbia}}
| rowspan="3" |{{flagcountry|Ottoman Empire}}
|-
|December 3, 1914
|{{flagcountry|Kingdom of Montenegro}}
|-
|December 5, 1914
|{{flagcountry|Empire of Japan}}
|-
|May 23, 1915
| rowspan="3" |{{flagcountry|Kingdom of Italy}}
| rowspan="1" |{{flagcountry|Austria-Hungary}}
|-
|August 21, 1915
|{{flagcountry|Ottoman Empire}}
|-
|August 28, 1916
|{{flagcountry|German Empire}}
|-
|October 14, 1915
||{{flagcountry|Kingdom of Bulgaria}}
|{{flagcountry|Kingdom of Serbia}}
|-
| rowspan="2" |October 15, 1915
|{{flagcountry|British Empire}}
| rowspan="6" |{{flagcountry|Kingdom of Bulgaria}}
|-
|{{flagcountry|Kingdom of Montenegro}}
|-
| rowspan="2" |October 16, 1915
|{{flagcountry|Empire of Japan}}
|-
|{{flagcountry|France|1794}}
|-
| rowspan="2" |October 19, 1915
|{{flagcountry|Kingdom of Italy}}
|-
|{{flagcountry|Russian Empire}}
|-
|March 9, 1916
|{{flagcountry|German Empire}}
| rowspan="2" |{{flagcountry|Portugal}}
|-
|March 15, 1916
|{{flagcountry|Austria-Hungary}}
|-
| rowspan="2" |August 28, 1916
|{{flagcountry|Kingdom of Romania}}
| {{flagcountry|Austria-Hungary}}
|-
|{{flagcountry|German Empire}}
| rowspan="3" |{{flagcountry|Kingdom of Romania}}
|-
|August 30, 1916
|{{flagcountry|Ottoman Empire}}
|-
|September 1, 1916
||{{flagcountry|Kingdom of Bulgaria}}
|-
|April 6, 1917
|{{flagcountry|United States|1912}}
| rowspan="3" |{{flagcountry|German Empire}}
|-
| rowspan="2" |April 7, 1917
|{{flagcountry|Panama}}
|-
|{{flagcountry|Cuba}}
|-
| rowspan="4" |June 27, 1917
| rowspan="4"|{{flagcountry|Kingdom of Greece|state}}
|{{flagcountry|Austria-Hungary}}
|-
|{{flagcountry|German Empire}}
|-
||{{flagcountry|Kingdom of Bulgaria}}
|-
|{{flagcountry|Ottoman Empire}}
|-
|July 22, 1917
| rowspan="2" |{{flagcountry|Thailand|name=Siam}}
|{{flagcountry|Austria-Hungary}}
|-
|July 22, 1917
| rowspan="2" |{{flagcountry|German Empire}}
|-
|August 4, 1917
||{{flagcountry|Liberia}}
|-
|August 14, 1917
| rowspan="2" |{{flagicon|Republic of China (1912–1949)|1912}} China
|{{flagcountry|Austria-Hungary}}
|-
|August 14, 1917
| rowspan="2" |{{flagcountry|German Empire}}
|-
|October 26, 1917
|{{flagcountry|Brazil}}
|-
|December 7, 1917
|{{flagcountry|United States|1912}}
| rowspan="2" |{{flagcountry|Austria-Hungary}}
|-
|December 10, 1917
|{{flagcountry|Panama}}
|-
|April 23, 1918
|{{flagcountry|Guatemala}}
|{{flagcountry|German Empire}}
|-
|May 6, 1918
| rowspan="2" |{{flagcountry|Nicaragua|1908}}
|{{flagcountry|Austria-Hungary}}
|-
|May 6, 1918
| rowspan="4" |{{flagcountry|German Empire}}
|-
|May 23, 1918
|{{flagcountry|Costa Rica|state}}
|-
|July 12, 1918
|{{flagcountry|Haiti}}
|-
|July 19, 1918
|{{flagcountry|Honduras}}
|}

== See also ==

* United Kingdom declaration of war upon Germany (1914)
* United States declaration of war on Germany (1917)
* United States declaration of war on Austria-Hungary

==References==
{{Reflist|2}}

[[Category:Laws of war|declaration]]

{{Sourceattribution|Declarations of war during World War I|1}}