World War I By GiorgiaFrigerio97 Jun 28, 1914 Archduke Francis Ferdinand is assassinated. Jul 28, 1914 Austria-Hungary declares war on Serbia, beginning World War I. Sep 9, 1914 Allied forces halt German advance into France during First Battle of the Marne. May 23, 1915 Italy declares war on Austria-Hungary. Jul 1, 1916 Allied offensive begins the Battle of the Somme. Apr 6, 1917 The United States declares war on Germany. Mar 3, 1918 Russia signs the Treaty of Brest-Litovsk with Germany. Nov 11, 1918 Germany signs the Armistice at Compiègne, ending World War I.
