Causes of World War I corrective." British Diplomat Arthur Nicolson wrote in May 1914, “Since I have been at the Foreign Office I have not seen such calm waters.” On 28 June 1914, Archduke Franz Ferdinand of Austria, heir presumptive to the Austro-Hungarian throne, and his wife, Sophie, Duchess of Hohenberg, were shot dead, by two gun shots in Sarajevo by Gavrilo Princip, one of a group of six assassins (five Serbs and one Bosniak) coordinated by Danilo Ilić, a Bosnian Serb and a member of the Black Hand secret society. The assassination is significant because it was perceived by Austria-Hungary as an existential challenge
Archduke Wilhelm Franz of Austria Archduke Wilhelm Franz of Austria Archduke Wilhelm Franz Karl of Austria-Teschen (German: Erzherzog Wilhelm Franz Karl von Habsburg-Lothringen, 21 April 1827 – 29 April 1894) was an Archduke of Austria from the House of Habsburg. He was born in Vienna as the son of Archduke Charles, Duke of Teschen (1771–1847) and Princess Henrietta of Nassau-Weilburg (1797–1829). He was a grandson of Leopold II (1747–1792) and nephew of Franz II (1768–1835), the last two Holy Roman Emperors. He held the office of Grand Master of the Teutonic Knights from 1863 until his death in 1894. He gained the rank of "Feldzeugmeister"