In 682 the monks of Noirmoutier, at the request of the Bishop of Poitiers Ansoald, erected the Abbey of Saint Michael in the Herm on one of the limestone islands of the Picton Gulf.
Benedictine Abbey, it knew a rich and eventful history and many destructions and reconstructions over the centuries.
Became Royal Abbey in 1516. No monk has lived there since the French Revolution. It became private property in 1818.