How The Mont Saint Michel was controlled by the Vikings and Normand dukes.

In 933, the dukes of Normandy ceded the Cotentin Peninsula to the Viking Rollo and his descendants. The Mont Saint Michel Abbey, located on the peninsula, was subsequently controlled by Benedictine monks from Fontenelle.

From Vikings to Kings, early years of the Mont Saint Michel.

After many vicissitudes, the church started in 1020, was finished in 1135 by Bernard, a professed monk of the abbey of the Bee and a prior of Gremont, who ordered a beautiful, high and strong tower to be built on the four large pillars of the chancel.