World War I was a global war fought from 1914 to 1918, mainly in Europe. It began after the assassination of Archduke Franz Ferdinand in Sarajevo in 1914. Countries such as Britain, France, Germany, and Austria-Hungary were involved.

Much of the fighting took place in trenches dug into the ground, especially on the Western Front in France and Belgium. Soldiers used new weapons such as machine guns, tanks, and poison gas. Battles often lasted for months with little movement.

The war ended in 1918, and the Treaty of Versailles was signed in 1919. This treaty set new borders and rules after the conflict.