The murder of Ferdinand and his wife prompted Austria-Hungary to declare war against Serbia, in turn triggering the events that eventually led to the First World War. The couple had actually survived an earlier assassination attempt that day when someone launched a bomb at their car, but the grenade detonated behind them.
World War I (1914)
World War I was known as "the war to end all wars." It mobilized over 70 million military personnel and was one of the largest wars in history. The war began on July 28, 1914, and lasted four years, until November 11, 1918.
World War I was one of the most prominent turning points in the political, cultural, economic, and cultural climate across the globe. The war and its aftermath resulted in a number of uprisings and revolutions, including the dissolution of the Austro-Hungarian, German, Ottoman, and Russian Empires.
World War II (1939)
World War II lasted from September 1, 1939, until September 2, 1945. This war was considered the deadliest in all of human history, with casualties upwards of 85 million. After the war ended, the United Nations was formed to prevent future conflicts between the countries.