World War I took place between 1914 and 1918.
World War I was started when Gavrilo Princip, from Serbia, shot Archduke Franz Ferdinand, from Austria-Hungary.
The war was fought with trenches. The soldiers shot at each other with explosives containing poisonous gas and metal shrapnel, from inside the trenches. When a whistle was blown, the soldiers climbed out of the trenches to fight from no man’s land.
Soldiers who were really brave were awarded the Victoria Cross. An example of this was wounded soldiers rescuing other soldiers who were wounded.