The uncle of Slobodan Princip assassinated what Austrian leader?
Slobodan Princip:  He was the nephew of Gavrilo Princip. Gavrilo Princip:  He assassinated Archduke Franz Ferdinand of Austria and his wife, Sophie, in Sarajevo on 28 June 1914, setting off a chain of events that would lead to outbreak of the First World War.
Archduke Franz Ferdinand