In 1667, following the French law signed by Louis XIV entitled "Jus Devloutionis", a large part of the Spanish Netherlands and Franche-Comté was to be recognised as his (thereby being part of France). However, following a short war in 1667 and 1668, the Kingdom of France came out victorious and in the Treaty of Aix-la-Chapelle, these regions (among others) were handed over to France. However, before the cessation of hostilities, a new regiment of horse was being raised within the region, and was handed over to Louis de Bourbon, Dauphin of France (heir to the French throne). The reason for this appointment seems to be unknown, either because he was spontaneously chosen for this operation, or as a good courtier he had requested this favour. The new regiment, affectionately known as the Régiment des Chevaulégers du Dauphin (Dauphin's Regiment of Light Horse) was under command of the dauphin's sister, Louise, Mademoiselle de La Vallière, who already raised and oversaw the new unit for a short period.