Pierrepont

The House of Pierrepont took its name from its lordship in the Ile-de-France and was founded in the twelfth century, perhaps by Hugh de Montfelix, said to be a natural son of Count Theobald the Great of Champagne. In 1204 Robert I de Pierrepont wed Eustachie, heiress of Roucy, and ruled the county in her name.

His successors held Roucy through the thirteenth century. John IV was killed at Mons-en-Pevele in 1304 and John V at Crecy in 1346; John V also inherited Braine, thereafter joined to Roucy.

In 1370 countess Isabelle sold Roucy to Louis of Anjou, but her uncle Simon de Pierrepont asserted his line's right to buy it back and won a twenty-year lawsuit before the Parlement of Paris. The last count, John VI, fell at Agincourt in 1415. After his death the county passed to the House of Sarrebruck.