Archduke Franz Ferdinand Carl Ludwig Joseph Maria Austria (18 December 1863 – 28 June 1914) was the heir presumptive to the throne of Austria-Hungary. His assassination in Sarajevo precipitated Austria-Hungary's declaration of war against Serbia, which in turn triggered a series of events that eventually led to Austria-Hungary's allies and Serbia's declaring war on each other, starting World War I. Franz Ferdinand was born in Graz, Austria, the eldest son of Archduke Karl Ludwig of Austria (the younger brother of Franz Joseph and Maximilian) and of his second wife, Princess Maria Annunciata of Bourbon-Two Sicilies. In 1875, when he was eleven years old, his cousin Francis V, Duke of Modena died, naming Franz Ferdinand his heir on condition that he add the name "Este" to his own. Franz Ferdinand thus became one of the wealthiest men in Austria. In 1889, Franz Ferdinand's life changed dramatically. His cousin Crown Prince Rudolf committed suicide at his hunting lodge in Mayerling. This left Franz Ferdinand's father, Karl Ludwig, as first in line to the throne. Karl Ludwig died of typhoid fever in 1896. Henceforth, Franz Ferdinand was groomed to succeed to the throne.

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