1914-06-28 : 28 Jun __ Assassination of Archduke Franz Ferdinand 1914-07-28 : 28 July __ Austria-Hungary declares war on Serbia 1914-08-01 : 1 Aug __ Germany declares war on Russia 1914-08-03 : 3 Aug __ Germany declares war on France 1914-08-04 : 4 Aug __ UK declares war on Germany 1914-08-23 : 23 Aug __ Japan declares war on Germany 1914-10-29 : 29 Oct __ Ottoman Empire enters the war 1915-05 : Italy joins the Allies 1917-04-06 : The US enter the war
