Who declared war on whom?

1914
Date Declared by Against whom
July 28 Austria-Hungary Serbia
August 1 Germany Russia
August 3 Germany France
August 4 United Kingdom Germany
August 5 Montenegro Austria-Hungary
August 6 Austria-Hungary Russia
August 6 Serbia Germany
August 9 Montenegro Germany
August 11 France Austria-Hungary
August 12 United Kingdom Austria-Hungary
August 22 Austria-Hungary Belgium
August 23 Japan Germany
August 25 Japan Austria-Hungary
November 1 Russia Ottoman Empire
November 3 Montenegro Ottoman Empire
November 5 United Kingdom Ottoman Empire
November 5 France Ottoman Empire
November 11 Sultan Mehmed V Declares 'Jihad' on all The Allied forces

1915
May 23 Italy Austria-Hungary
October 14 Bulgaria Serbia
October 15 United Kingdom Bulgaria
October 16 France Bulgaria
October 19 Italy and Russia Bulgaria

1916
March 9 Germany Portugal
April 23 Irish Rebels United Kingdom (The Easter Rising)
August 27 Italy Germany

1917
April 6 United States Germany
June 30 Greece The Central Powers (Germany, Austria-Hungary, Bulgaria, Ottoman Empire)
December 7 United States Austria-Hungary

1918
November 11 Hostilities cease