The House of Croÿ () is a family of European mediatized nobility, which held a seat in the Imperial Diet from 1486, and was elevated to the rank of Princes of the Holy Roman Empire in 1594. In 1533 they became Dukes of Arschot (in Belgium) and in 1598 Dukes of Croy in France. In 1913, the family had branches in Belgium, France, Austria and Prussia. This dynastic house, which originally adopted its name from the Château de Crouy-Saint-Pierre in French Picardy, claimed descent from the Hungarian Prince Marc, (if true, he was likely a grandson of Prince Géza) who allegedly settled in France in 1147, where he married an heiress to the barony of Croÿ. The Croÿ family rose to prominence under the Dukes of Burgundy. Later, they became actively involved in the complex politics of France, Spain, Austria, and the Low Countries. Among the more illustrious members of the House of Croÿ were two bishop-dukes of Cambrai, two cardinals (one being also the Archbishop of Toledo and another being the Archbishop of Rouen), five bishops (those of Thérouanne, Tournai, Cammin, Arras, and Ypres), one prime minister of Philip the Good, one finance minister, archchancellor, chief admiral, godfather and tutor of Holy Roman Emperor Charles V (himself godfather to another Croÿ), one Grand-Bouteiller, one Grand-Maitre and one Marshal of France; one Grand Equerry of the King of Spain, several imperial field marshals and twenty generals, four finance ministers of the Netherlands, two governors of the Netherlands and Belgium, one Russian field marshal; numerous ministers, ambassadors and senators in France, Austria, Belgium, and a record of thirty-two knights of the Order of the Golden Fleece. The head of the house bears the title of duke, with all the other members titled as princes or princesses. All of them bear the predicate of Serene Highness. The Croÿs of Burgundy Jean I de Croÿ was responsible for the ascendancy of his family to a position of supreme power in medieval Burgundy. He served Philip the Bold and his son John the Fearless in the capacity of councillor and chamberlain. In 1384 he married a wealthy heiress, Marie de Craon, successfully suing her first husband's family upon her death. In 1397, Jean acquired the lordship of Chimay, which was to become a core dominion of the Croÿ family. Four years later, he was appointed governor of Artois and led the ducal armies against