Franz Ferdinand's assassination refers to the killing of Archduke Franz Ferdinand of Austria and his wife Sophie on June 28, 1914, in Sarajevo by Gavrilo Princip, a member of the nationalist group known as the Black Hand. This event is widely recognized as the immediate catalyst for World War I, triggering a series of political alliances and conflicts that ultimately led to a global war. The assassination heightened tensions between Austria-Hungary and Serbia, setting off a chain reaction of events fueled by militarism, nationalism, and the complex web of alliances in Europe at the time.