Timeline of the events
June 28, 1914 - Archduke Franz Ferdinand is assassinated in Sarajevo
July 23, 1914 - Austro-Hungarian government's ultimatum on Serbia
July 28, 1914 - Austro-Hungary declares war on Serbia
August 1, 1914 - Russia and French mobilized in the war
August 4, 1914 - Britain issues an ultimatum to Germany
July 23, 1914 - Austro-Hungarian government's ultimatum on Serbia
July 28, 1914 - Austro-Hungary declares war on Serbia
August 1, 1914 - Russia and French mobilized in the war
August 4, 1914 - Britain issues an ultimatum to Germany