The assassination of Archduke Franz Ferdinand was primarily caused by tensions in the Balkans, escalating nationalism, and political strife. The archduke's visit to Sarajevo on June 28, 1914, provoked anger among Serbian nationalists, who saw him as a symbol of Austro-Hungarian oppression. This led to his assassination by Gavrilo Princip, a member of the nationalist group Black Hand. The event triggered a series of diplomatic crises that ultimately culminated in the outbreak of World War I, reshaping global politics.