The Duchy of Parma was a small Italian state between 1545 and 1802, and again from 1814 to 1860.
The Duke of Parma was also Duke of Piacenza, except for the first years of the rule of Ottavio Farnese (1549-1556), and the rule of the two dukes appointed by Napoleon in 1808.
Farnese Dukes of Parma, 1545-1731
Bourbon Dukes of Parma, 1731-1735
Habsburg Dukes of Parma, 1735-1748
Bourbon Dukes of Parma, 1748-1802
Napoleonic Dukes, 1808-1814
Habsburg Dukes of Parma, 1814-1847
Bourbon Dukes of Parma, 1847-1860
Bourbon Dukes of Parma since 1860