Foreign Office brings World War 1 diplomacy to life online with podcasts and live tweets. To mark 100 years to the day that the Archduke Franz Ferdinand was assassinated in Sarajevo, on 28 June the FCO will bring the events leading up to the outbreak of war vividly to life online. Known as the ‘July crisis’, the assassination sparked a diplomatic frenzy and, ultimately, led to the outbreak of World War 1 on 28 July 1914, with Great Britain joining the war on 4 August.