Montebourg Abbey was probably established by William the Conqueror after the invasion to England (1066). The exact date is unknown, but it was before William's death in 1087. The abbey got lot of donations from the Dukes of Normandy and Kings of England until the 1180s. It had a large land property even in the southern England and the abbey grew up quickly in the 12th century.
The abbey suffered damages in the Hundred Years' War, but it was renovated in the mid-15th century. In 1562 Huguenots looted the abbey during the Frencg Wars of Religion. The first school in Montebourg was established in 1585 and in the 18th century it was used as Catholic poor house and rest home. But soon after the Great Revolution caused the decline of Montebourg Abbey. It was reduced to the state and monastic buildings were partially demolished. In 1842, the Vicar General of Coutances acquired what was by then only an enclosure of ruins, and set it up for the Brothers of Mercy, which he had just formed in order to promote Catholic education in the countryside. From there, the brothers have continued their work.
References:Kakesbeck is one of the largest medieval fortifications in Münsterland and the oldest castle in Lüdinghausen. The imposingly grown complex originated in 1120 as a motte, a small hilltop tower castle. After numerous changes of ownership, the castle was extended onto two islands, but it was not until the 14th century that it underwent significant alterations and extensions under the von Oer family. The estate experienced its heyday in the middle of the 18th century, when it covered an area of almost one square kilometre and consisted of five further outer castles in addition to the core castle, which were secured by ramparts and moats.
The well-maintained condition of the castle today is thanks to the late Wilfried Grewing, the former lord of the castle. The foundation named after him has been particularly committed to preserving the property since 2020.