Prince de Joinville

The first known lord of Joinville (French Sire or Seigneur de Joinville) in the county of Champagne appears in the middle of the eleventh century. The lordship was raised into a principality by Henry II in 1551. It lasted until the abolition of feudalism in 1789. The title Prince of Joinville (French Prince de Joinville) continues in use as a courtesy title to this day.

Joinville (from medieval Latin Jonivilla or Junivilla) lies on the river Marne in eastern Champagne. In the early eleventh century, when a castle was built or possibly just enlarged at the site, it lay close to the border between the Kingdom of France and the Holy Roman Empire. The family of the lords of the castle rose to prominence late in the eleventh century when they acquired a second castle of Vaucouleurs. From then on the lord of Joinville, as one of the few "multicastle" lords in Champagne, regularly attended the court of his superior, the count of Troyes. Lord Geoffrey III followed Count Henry I on the Second Crusade (1147–49) and afterwards was appointed seneschal of Champagne (1152), an office that became hereditary in his family.

The Joinville family patronised the Cistercian monasteries of Clairvaux and La Crête, but their relationship with the nearby Benedictine house of Montier-en-Der was one of rivalry. The family also had influence in local cathedral chapters. Guy was elected bishop of Châlons (1164–90) with the help of Count Henry I, and William became bishop of Langres (1209–19).

...
Wikipedia