House of the Royal Family

Orléans is the name used by several branches of the Royal House of France, all descended in the legitimate male line from the dynasty's founder, Hugh Capet. It became a tradition during France's ancien régime for the dukedom of Orléans to be granted as an appanage to a younger son of the king. While each of the Orléans branches thus descended from a junior prince, they were always among the king's nearest relations in the male line, sometimes asipiring and sometimes succeeding to the throne itself.The last cadet branch to hold the ducal title descended from Henri de Bourbon, duc de Vendôme, who became king in 1589, and is sometimes known as the "House of Bourbon-Orleans" (Maison de Bourbon-Orléans). From 1709 until the French Revolution the Orléans dukes were next in the order of succession to the French throne after members of the seniormost branch of the House of Bourbon, descended from Louis XIV. Louis XIII's younger brother and younger son were granted the dukedom successively in 1626 and 1660, and since they had contemporaneous living descendants, there were actually two Bourbon-Orléans branches at court during the reign of Louis XIV.The elder of these branches consisted of Gaston, duc d'Orléans, younger son of Henri IV, and the four daughters of his two marriages. The junior and final House of Orléans descended from Philippe I, Duke of Orléans.
Upon the death of Gaston of Orléans, the appanage of the Duchy of Orléans reverted back to the crown. The appanage was given to Philippe, the brother of Louis XIV of France.It was Philippe and his second wife, the famous court writer Elizabeth Charlotte of the Palatinate, who founded the modern House of Orléans - their surviving son being the regent of France for the young Louis XV.As a fils de France, Philippe's surname was "de France". Upon his death, his son inherited the Orléans dukedom, but as only a petit-fils de France his surname was taken from his father's main title, and was thus d'Orléans. The first two dukes, as son and patrilineal grandson, respectively, of a French king, were entitled to be addressed as Royal Highness.