The first abbey was built on Mont Castillon, some 7 km east of the current location of Saint-Mihiel. Circa 709 AD, a few monks settled on land that belonged to Count Wulfoad, administrator of this pagus in Austrasia. It was a small district which included a chapel that was probably dedicated to St. Michael since Wulfoad and his wife, Adalsinde, were deeply devoted to the archangel. Wulfoad’s assets, however, were confiscated by King Pepin and the Mont Castillon district was given to the monks of Saint-Denis Abbey. The first abbey dedicated to St. Michael was built in 755 AD.
Circa 815 AD, Smaradge, one of Charlemagne’s closest friends, moved the abbey to land at the confluence of the Rivers Marsoupe and Meuse. It was built more or less in a square and comprised a cloister and an inner courtyard. The name of Saint-Mihiel was first mentioned in a text in 1106 but it was probably in use before then. It is thought to have come from an alteration of the name “sanctis Michaelis”.