In World War I, the Austro-Hungarian Empire formally declared war on Russia on August 6, 1914. Already formally at war with the Kingdom of Serbia (since July 28th of that same year), the Empire's declaration made formal what was already a practical fact, with Russia, on one hand, and, on the other, Germany and the Austro-Hungarians already engaged in military conflict.
I will only list the more important countries involved in the war because there were many minor countries that are of very little importance to the war.Austria-Hungary declared war on Serbia July 28 1914Russia declared war on Austria-Hungary July 30 1914Germany declared war on Russia August 1 1914Germany declared war on France August 3 1914Germany declared war on Belgium August 4 1914Britain declared war on Germany August 4 1914Montenegro declared war on Austria-Hungary August 5 1914Serbia declared war on Germany August 6 1914Montenegro declared war on August 9 1914France declared war on Austria-Hungary August 11 1914Britain declared war on Austria-Hungary August 12 1914Austria-Hungary declared war on Belgium August 22 1914Japan declared war on Germany August 23 1914Japan declared war on Austria-Hungary August 25 1914Russia declared war on Ottoman Empire November 1 1914Serbia declared war on Ottoman Empire November 2 1914Montenegro declared war on Ottoman Empire November 3 1914Britain declared war on Ottoman Empire November 5 1914France declared war on Ottoman Empire November 5 1914Italy declared war on Austria-Hungary May 23 1915Italy declared war on Ottoman Empire August 21 1915Bulgaria declared war on Serbia October 14 1915Britain declared war on Bulgaria October 15 1915Montenegro declared war on Bulgaria October 15 1915France declared war on Bulgaria October 16 1915Italy declared war on Bulgaria October 19 1915Russia declared war on Bulgaria October 19 1915Romania declared war on Austria-Hungary August 27 1916Italy declared war on Germany August 27 1916Germany declared war on Romania August 28 1916Ottoman Empire declared war on Romania August 20 1916Bulgaria declared war on Romania September 1 1916United States declared war on Germany April 6 1917United States declared war on Austria-Hungary December 7 1917The Armistice occurred November 18 1918Note: where Britain is listed, this includes declarations of war by British Dominions also(Canada, Australia, New Zealand, South Africa and India), as they were not completely independent during the First World War and couldn't conduct Foreign Policy themselves.
The two atomic bombs were dropped August 6th and 9th, 1945. I'm almost certain Russia declared war on Japan and moved into occupied Manchuria on August 10th, but correction welcome.
WWI - Congress declared war on Germany on April 6, 1917 and Austria-Hungary on December 7, 1917. WWII - Congress declared war on Japan on December 8, 1941, and on Germany and Italy on December 11, 1941.
Dec 8th 1941 the day after Pearl Harbor
December 7th, 1941
1948/
I will only list the more important countries involved in the war because there were many minor countries that are of very little importance to the war.Austria-Hungary declared war on Serbia July 28 1914Russia declared war on Austria-Hungary July 30 1914Germany declared war on Russia August 1 1914Germany declared war on France August 3 1914Germany declared war on Belgium August 4 1914Britain declared war on Germany August 4 1914Montenegro declared war on Austria-Hungary August 5 1914Serbia declared war on Germany August 6 1914Montenegro declared war on August 9 1914France declared war on Austria-Hungary August 11 1914Britain declared war on Austria-Hungary August 12 1914Austria-Hungary declared war on Belgium August 22 1914Japan declared war on Germany August 23 1914Japan declared war on Austria-Hungary August 25 1914Russia declared war on Ottoman Empire November 1 1914Serbia declared war on Ottoman Empire November 2 1914Montenegro declared war on Ottoman Empire November 3 1914Britain declared war on Ottoman Empire November 5 1914France declared war on Ottoman Empire November 5 1914Italy declared war on Austria-Hungary May 23 1915Italy declared war on Ottoman Empire August 21 1915Bulgaria declared war on Serbia October 14 1915Britain declared war on Bulgaria October 15 1915Montenegro declared war on Bulgaria October 15 1915France declared war on Bulgaria October 16 1915Italy declared war on Bulgaria October 19 1915Russia declared war on Bulgaria October 19 1915Romania declared war on Austria-Hungary August 27 1916Italy declared war on Germany August 27 1916Germany declared war on Romania August 28 1916Ottoman Empire declared war on Romania August 20 1916Bulgaria declared war on Romania September 1 1916United States declared war on Germany April 6 1917United States declared war on Austria-Hungary December 7 1917The Armistice occurred November 18 1918Note: where Britain is listed, this includes declarations of war by British Dominions also(Canada, Australia, New Zealand, South Africa and India), as they were not completely independent during the First World War and couldn't conduct Foreign Policy themselves.
The Crimean War began on October 4, 1853, when the Sultan of the Ottoman Empire declared war on Russia. Some histories date the war from March 28, 1854, when Great Britain declared war on Russia and joined in the war.
September, 2 1945
1st September, 1939 (Declared on the 3rd) to the date of Hitler's death, 30th April, 1945.
June 21st 1914
December 12, 1941
Russia's date of orgin is 1801
The two atomic bombs were dropped August 6th and 9th, 1945. I'm almost certain Russia declared war on Japan and moved into occupied Manchuria on August 10th, but correction welcome.
WWI - Congress declared war on Germany on April 6, 1917 and Austria-Hungary on December 7, 1917. WWII - Congress declared war on Japan on December 8, 1941, and on Germany and Italy on December 11, 1941.
WWI - Congress declared war on Germany on April 6, 1917 and Austria-Hungary on December 7, 1917. WWII - Congress declared war on Japan on December 8, 1941, and on Germany and Italy on December 11, 1941.
WWI - Congress declared war on Germany on April 6, 1917 and Austria-Hungary on December 7, 1917. WWII - Congress declared war on Japan on December 8, 1941, and on Germany and Italy on December 11, 1941.