Who was Gavrilo Princip and what role did he play in the start of World War I?

Gavrilo Princip was a South Slav nationalist born into a Bosnian Serb peasant family. He was a member of a revolutionary movement that sought to end Austro-Hungarian rule in the Balkans and unite the South Slav peoples into a federal nation. To achieve this, he was trained in terrorism by the Black Hand, a Serbian secret society.12

Princip played a pivotal role in the start of World War I by assassinating Archduke Franz Ferdinand, the heir to the Austro-Hungarian throne, and his wife, Sophie, in Sarajevo on June 28, 1914. This act provided Austria-Hungary with the justification it sought to open hostilities against [Serbia]. Consequently, Austria-Hungary declared war on Serbia on July 28, 1914, triggering a chain reaction of alliances that escalated the conflict into a global war.123

Following the assassination, Princip was arrested and sentenced to 20 years in prison, where he died of tuberculosis in 1918.123