Germany developed the Schlieffen Plan
Germany declared war on France and invaded neutral Belgium.
France and Britain halted German forces in northern France. The Western Front was established.
German fleet trapped in its ports by British blockade.
South Africa captured South-West Africa; Australia took German New Guinea; Japan seized Germany's Pacific Island colonies and territories in China.
Russia captured Armenia. Turkish soldiers rounded up Armenians for the long death march and massacre. Turkey's Middle Eastern colonies became a theatre of war.
Allies landed at Gallipoli.
Italy joined the Allies.
German and Austrian troops overran Romania.
Easter uprising in Ireland, attack on Dublin Post Office.
U-boats began to attack ships of neutral countries.