Christopher Plummer in The Assassination at Sarajevo (1975)
Archduke Franz Ferdinand Carl Ludwig Joseph Maria of Austria. Death by assassination. The assassinations, along with the arms race, nationalism, imperialism, militarism, and the alliance system all contributed to the origins of World War I, which began a month after Franz Ferdinand's death, with Austria-Hungary's declaration of war against Serbia. The assassination of Ferdinand is considered the most immediate cause of World War I.