Ferdinand I (Ferdinando Maria Filippo Lodovico Sebastiano Francesco Giacomo; 20 January 1751 – 9 October 1802) was Duke of Parma, Piacenza and Guastalla from his father's death on 18 July 1765 until he ceded the duchy to France by the Treaty of Aranjuez on 20 March 1801. He was a member of the Spanish House of Bourbon. Early life Born at the Ducal Palace of Colorno as the second child and only son of Philip, Duke of Parma and Princess Louise Élisabeth of France, he was considered to be the favorite grandson of his maternal grandfather King Louis XV of France. As a grandson in the male line of King Philip V of Spain, he was created an infante of Spain upon his father's death. As a grandson of King Louis, Ferdinand was also a direct descendant of England's William the Conqueror. As the heir to one of the largest collection of sovereign duchies, Ferdinand was an attractive candidate for many royal ladies of Europe. Probable candidates included Princess Maria Beatrice Ricciarda of Modena, daughter of Ercole III d'Este and (like Ferdinand) an in law of Marie Antoinette. She was, through her mother, heiress to the Duchy of Massa and Carrara, but despite being the last descendant of the Este, she was not also the heiress to the Duchy of Modena and Reggio due to the Salic law that was in force there. Ferdinand's possible marriage to Princess Maria Beatrice was, however, very unlikely since the latter had been engaged to Archduke Leopold of Austria at a very young age and later on to Leopold's younger brother Archduke Ferdinand upon the death of an older brother, Archduke Charles. It is likely that a union between Parma and Modena was only promoted in vain by Parma's minister, Guillaume du Tillot, since the engagement of Modena's princess to an Austrian Archduke was already agreed very early on. Another candidate was Louise Marie Thérèse Bathilde d'Orléans who offered a very large dowry; she was the only surviving daughter of Louis Philippe I, Duke of Orléans and the sister of Philippe Égalité. The decision of who his future spouse would be was sealed by his mother's close correspondence with the powerful Empress Maria Theresa of Austria, who had promised Ferdinand's parents the throne of the Netherlands, which had been returned to Austrian rule under the Treaty of Aix-la-Chapelle. This never occurred and, as a