The Treaty of Aranjuez was signed on 21 March 1801 between France and Spain. The accord confirmed the terms of the Treaty of San Ildefonso (1 October 1800).
Moreover, the King of Spain promised to get his relative, Ferdinand, Duke of Parma, to agreed to cede Parma to France in exchange for an "honorable indemnity". The Grand Duchy of Tuscany was to go to Ferdinand's son Louis, who was also to receive the Principality of Piombino together with the title "King of Etruria". The incumbent Grand Duke of Tuscany, Ferdinand III, was to be compensated with the secularized territories of the Archbishopric of Salzburg. The Tuscan portion of the island of Elba, mainly the fortified town of Portoferraio, was to be ceded to France, although at the time it was under English occupation. In implementation some of these clauses were altered. By the Treaty of Florence (28 March 1801), King Ferdinand IV of Naples ceded Piombino and the State of the Presidi in southern Tuscany to France, which kept Piombino and handed the Presidi over to the new Kingdom of Etruria. The duke of Parma was allowed to keep his throne until his death (9 October 1802).