Born Leopoldo of Naples and Sicily, he was the sixth son of Ferdinand IV of Naples[1] and his wife Maria Carolina of Austria, daughter of Maria Theresa of Austria.

Leopold married his niece & double-first cousin once removed Archduchess Clementina of Austria, third surviving daughter of Francis II, Holy Roman Emperor (later Francis I of Austria) and his sister Maria Teresa of Naples and Sicily on 28 July 1816 at Schönbrunn Palace in Vienna.

Leopold and Clementina had four children but only their daughter Princess Maria Carolina survived infancy.

Leopold also had an extramarital affair with the Viennese dancer Fanny Elssler, which led to the birth of an illegitimate son, Franz, born in 1827 and died by suicide in 1873.

His wife, Clementina, died thirty years later, at the age of eighty-three.