SMS Kaiser Karl VI and Argentina. On 25 May, she represented Austria-Hungary at the centennial of Argentina's May Revolution, which won the country's independence from Spain. On 28 June 1914, Archduke Franz Ferdinand, the heir to the Austro-Hungarian throne, was assassinated in Sarajevo; the assassination sparked the July Crisis and ultimately the First World War, which broke out a month later on 28 July. The German battlecruiser , which had been assigned to the Mediterranean Division, sought the protection of the Austro-Hungarian fleet, and so Admiral Anton Haus sent the fleet, including "Kaiser Karl VI", south on 7 August to assist his German ally.
Robert, Archduke of Austria-Este assassinated relative Archduke Franz Ferdinand of Austria, (1863–1914), who had inherited in 1875 the Austria-Este designation and what had been salvaged of the Este fortune when the duchy was annexed to Italy in 1860. Archduke Robert descended through his Habsburg father from Ercole III d'Este, Duke of Modena, and his mother Zita was a descendant of Maria Beatrice d'Este, heiress of Modena and her husband, Archduke Ferdinand of Austria. Thus the lineage of the last Este dukes, in female descent, remained joined to the Austria-Este legacy. Archduke Robert eventually adopted use for himself and his descendants in male line the