World War I was a four year long war, and it all started in 1914 when Archduke Franz Ferdinand of Austria was assassinated by a member of the Black Hand, a secret terrorist group from Serbia.
War on the Eastern Front was different from war on the Western Front in WWI. The Western Front was mostly characterized by trench warfare, and the Eastern Front was much larger, and didn’t use trench warfare.
World War I had stopped when Germany surrendered from on November 11th, 1918. The war officially ended on June 28th, 1919 when Germany and the Allied Nations signed the Treaty of Versailles.
World History Blog 