Gavrilo Princip (25 July 1894 – 28 April 1918) was a Bosnian Serb member of Young Bosnia, a Yugoslavist organization seeking an end to Austro-Hungarian rule in Bosnia and Herzegovina. At the age of 19, he assassinated Archduke Franz Ferdinand of Austria and Ferdinand's wife, Sophie, in Sarajevo on 28 June 1914, initiating a chain of events that led to the outbreak of World War I.

Princip and his accomplices were arrested and implicated the Serbian nationalist secret society known as the Black Hand, leading Austria-Hungary to issue a démarche to Serbia known as the July Ultimatum. During Princip's trial he stated: "I am a Yugoslav nationalist, aiming for the unification of all Yugoslavs, and I do not care what form of state, but it must be freed from Austria."

He said the archduke was targeted because "as future Sovereign he would have prevented our union by carrying through certain reforms," an allusion to the archduke's reputed support for structural reforms of the monarchy that would assign more autonomy to the Slavic lands.

Princip died on 28 April 1918 from tuberculosis exacerbated by poor prison conditions which had cost him his right arm.

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