Around the year 990, we believe the first timber building of Maison Forte des Carteret was placed in close proximity to St Louis Chapel. The timber construction was erected. A flooded mote ditch encircled the area of the site. Guy de Carteret called L’Oiseleur (Bird Man) was its first owner. Over the years the dwelling was converted into a Manor House which was built in stone complete with a Chapel and outbuildings. The Carteret family at that time were also the Seigneurs of the Parish of Saint Ouen in Jersey.
Between 1348 and 1723 the property of the Manor in Carteret was no longer inhabited by the Seigneurial family nor by the purchasers of the Fief-Ferme. The property deteriorated and fell in ruins except for the Chapel of St Louis.
In 1723 the Manoir du Havre was built on the site.