Ferdinand I of the Two Sicilies

Ferdinand I (12 January 1751 – 4 January 1825) was King of the Two Sicilies from 1816 until his death. Before that he had been, since 1759, King of Naples as Ferdinand IV and King of Sicily as Ferdinand III. He was deposed twice from the throne of Naples: once by the revolutionary Parthenopean Republic for six months in 1799, and again by a French invasion in 1806, before being restored in 1815 at the end of the Napoleonic Wars.

Ferdinand was the third son of King Charles VII of Naples and III of Sicily by his wife, Maria Amalia of Saxony. On 10 August 1759, Charles succeeded his elder half-brother, Ferdinand VI, becoming King Charles III of Spain, but treaty provisions made him ineligible to hold all three crowns. On 6 October, he abdicated his Neapolitan and Sicilian titles in favour of his third son, because his eldest son Philip had been excluded from succession due to imbecility and his second son Charles was heir-apparent to the Spanish throne. Ferdinand was the founder of the cadet House of Bourbon-Two Sicilies.