The document summarizes key events leading up to and during World War 1:
- Tensions rose in Europe due to militarism, imperialism, nationalism and alliances between countries.
- The assassination of Archduke Franz Ferdinand of Austria-Hungary by a Serbian nationalist in 1914 triggered Austria-Hungary to declare war on Serbia and led Germany to enter the war in support of Austria-Hungary.
- Major events of WWI included Germany invading Belgium and Britain entering the war in 1914, the Battle of the Somme in 1916, and US entry into the war in 1917 which helped ensure an Allied victory. Germany signed an armistice in 1918 and the Treaty of Versailles formally ended the war