World War One Timeline

Key events

Assasination of Archduke Franz Ferdinand

June 28, 1914

Archduke Franz Ferdinand was assassinated in Austria-Hungary by Gavrilo Princip, a member of the extremist group, the Black Hand.

Lusitania is sunk

May 7, 1915

The vessel Lusitania is sunk by German U-boats, which causes the United States to take interest in the war for the first time.

Sussex Pledge

May 4, 1916

Germany is forced to sign the Sussex pledge stating that they will not blindly shoot ships anymore and will at the least inspect them for enemy war cargo before deciding if it stays or goes by the United States.

Sussex Pledge is broken

February 1 1917

Germany breaks the Sussex pledge, which lead to the next war declaration.

Armstice signed

November 11, 1918

The war is brought to a close.

Paris Peace Conference Held

January 19, 1919

Many nations gather to discuss bringing about peace in Europe. The Treaty of Versailles is written up demanding Germany keep no armies, hold little territory, and replace everyone's navy, effectively destroying its economy. Germany complies to an extent, refusing to replace everyone's navy.

War Declarations

First War Declarations

June 28, 1914 - August 12, 1914

Austria-Hungary declares war on Serbia on June 28th, Germany on France on August 3rd, Belgium on August 4th, Britain on Germany on the 4th, Austria Hungary on Russia on August 6th, France and Britain against Austria-Hungary on the 12th.

Italy declares war on Austria-Hungary

May 23, 1915

Despite orders from the Central Powers, Italy declares war on Austria-Hungary.

The United States declares war on Germany

April 6, 1917

The United States declares war on Germany in response to their breaking of the Sussex pledge.


Battle of Marne

September 5,1914 - September 10, 1914

The French and British conducted this battle in a successful attempt to thwart the Schlieffen plan. The Germans were driven back and much ground was recovered.

Second Battle of Ypres

April 22, 1915 - May 25, 1915

The first battle in which chlorine gas was deplored. Germans used it against the Russians at Ypres.


June 29, 1915 - November 7, 1917

Italy fights Austria-Hungary over the span of twelve battles over borders. Even when other nations step in to back up both sides, little gets achieved.

Battle of Verdun

February 21, 1916 - December 2, 1916

The Germans attempt to take Verdun, a spot that was of great value to the French. The battle brought little success for either side involved.

Battle of Jutland

May 31, 1916 - June 1, 1916

The largest Naval battle in the war during which the British and the German fleets. The British defeated the Germans.

Brusilov Offensive

June 4, 1916 - September 20, 1916

The Brusilov Offensive was a Russian Offensive against the Germans as a means of weakening them and keeping them out of Verdun. The Austrio-Hungarian army was laid waste to during this battle and Austria-Hungary lost its status as major military power as a result.

The Battle of Somme

July 1, 1916 - November 18, 1916

Incredibly bloody battle between Germans and French. Brought to a close by snow.

The Second Battle of Marne

July 15, 1918 - August 5, 1918

Germany's last stand in the war-- saw Germany defeated again by French after disastrous attempts to bring down their army. The German army is left in a crippled state.