The assassination of Franz Ferdinand happened in Serbia and happened because Gavrilo Princip of The Serbian nationalist shot him because he wanted the independence of Serbia from Austria Hungary. This instead started the spark of World War 1.

A month after the assassination of Franz Ferdinand, Austria Hungary declares war on Serbia. This lead to the start of World War 1.

Germany declares war on Russia, France and Belgium.
Britain declares war on Germany.
Austria-Hungary declares war on Russia.
France and Britain declare war on Austria-Hungary.
Japan declares war on Germany.
Austria-Hungary declares war on Belgium.
The United States declares its neutrality.

The United States was neutral until the disaster was the Lusitania disaster where a British passenger liner that carried 1198 people was sunken by a german u boat. This caused Americans to turn against Germany and the central power.

The first battle of Somme lasted until mid November. The British suffered lots of casualties of that totaled 1.2 million with only 7 miles of ground was gained

On April 2nd, 1917 President Wilson declared war on the central powers and joined the allied power, which changed the war.

On November 3, 1918 Germany and Austria Hungary surrendered to the allies and signed a truce to end the Great War.

The treaty established nine new nations that include Poland, Czechoslovakia, and Yugoslavia. Also it broke up the Austria Hungary empire. Lastly it greatly affected Germany because it prevented them from creating a lasting peace in Europe, made them admit they where responsible for the war and made them pay 33 billion dollars in reparation.