Ferdinand became Governor of the Duchy of Milan on his marriage in 1771, as long as his father-in-law
Ercole III d'Este still ruled the
Duchy of Modena. He and his family lived in
Milan. In 1780, Ferdinand was confirmed as Governor of
Lombardy by his brother, the new Holy Roman Emperor
Joseph II. In 1796,
Napoleon's invasion of Milan forced the family to flee the French forces. Duke Ercole III also had to flee Modena, which overthrew the monarchy and joined the
Cisalpine Republic. By the
Treaty of Campo Formio in 1797, Duke Ercole III was granted the Duchy of
Breisgau, a Habsburg territory in southwest Germany. When Ercole III died in 1803, Ferdinand succeeded as Duke of Breisgau, as well as "
titular Duke" of Modena and Reggio. By the
Treaty of Pressburg in 1805, Ferdinand ceded the Duchy of Breisgau to the
Grand Duchy of Baden. Ferdinand died the following year in Vienna, on 24 December. He is buried in the
Imperial Crypt in Vienna. In 1814, Ferdinand's eldest surviving son, Francis IV, was recognised as Duke of Modena by the
Congress of Vienna. ==Ancestry==