1975 Czech film
The Day That Shook the World (Serbo-Croatian: Sarajevski atentat, lit. The Sarajevo Assassination) is a 1975 Czechoslovak-Yugoslav-German co-production film directed by Veljko Bulajić, starring Christopher Plummer and Florinda Bolkan. The film is about the assassination of Archduke Franz Ferdinand and his wife Sophie in Sarajevo in 1914 and the immediate aftermath that led to the outbreak of World War I.
When the only surviving heir to Emperor Franz Joseph of Austria-Hungary, Archduke Franz Ferdinand, was killed by Gavrilo Princip, a Yugoslav nationalist, on 28 June 1914, his death set in motion a chain of events that resulted in the First World War. The movie chronicles the events surrounding that death and its aftermath. The assassination gave the Germans and Austrians reason to fear that the Russian Empire was actively fomenting unrest in the Balkans, since Serbia was a bone of contention throughout the region.
Plot summary adapted from Wikipedia, licensed under CC BY-SA 4.0.