The assassination of Archduke Franz Ferdinand of Austria-Hungary and his wife Sophie, Duchess of Hohenberg, on June 28, 1914, in Sarajevo, Bosnia, is considered to be the event that triggered the start of World War I. The assassin, Gavrilo Princip, was a member of a Serbian nationalist group seeking independence from Austria-Hungary, and the killing of the Archduke and his wife led to a domino effect of political and military alliances, ultimately resulting in the start of the war on August 4, 1914.