The abbey, dedicated to Saint Peter, Saint Paul and the Virgin Mary, was called Sanctus Petrus Fossatensis in Medieval Latin (Saint Pierre des Fossés in French), meaning "Saint Peter of the Moats". In 868, King Charles the Bald invited the monks of the Abbey of Saint-Maur de Glanfeuil (in Le Thoureil, Maine-et-Loire, western France), who had fled their abbey due to Viking invasion, to relocate to Saint Pierre des Fossés with their precious relics of Saint Maurus.
Later in the Middle Ages, the relics of Saint Maurus became very famous as they were supposed to heal gout and epilepsy, and Saint Pierre des Fossés became one of the most famous pilgrimage centers of medieval France. The rededication to Saint Maurus, in which abbey was renamed Saint-Maur-des-Fossés ("Saint Maurus of the Moats"), was justified by the story that during a drought in 1137, prayers to the Virgin and Saints Peter and Paul having been ineffective, prayer to Saint Maur brought the needed rainfall.
The Château de Saint-Maur, still in the possession of the Condé, was nationalised during the French Revolution, emptied of its contents, and its terrains divided up among real-estate speculators. The structure was demolished for the value of its materials; virtually nothing remains..
In 1791, part of the territory of Saint-Maur-des-Fossés was detached and became the commune of La Branche-du-Pont-de-Saint-Maur, later renamed Joinville-le-Pont.
After the abbey itself was abandoned, its church providing building materials in the town. During the French Revolution, Saint-Maur-des-Fossés was temporarily renamed Vivant-sur-Marne (meaning "Lively upon Marne") in a gesture of rejection of religion.
After the Revolution, the official name of the commune was simply Saint-Maur; it is only in 1897 that "des-Fossés" was re-added to the name, probably to conform to the historical name and also to distinguish Saint-Maur-des-Fossés from other communes of France also called Saint-Maur. In 1924, a few vestiges of the abbey were collected in the newly-established Musée du vieux Saint-Maur.
Crooner Charles Trenet, whose ‘La Mer’ has been recorded 400 times (notably as ‘Beyond The Sea’ by Bobby Darin), was a longtime resident: the bronze hat at the foot of the lovers' statue on the Quai Winston Churchill is dedicated to him. Other French stars who have lived in Saint-Maur include Vanessa Paradis, Françoise Hardy, Raymond Devos, Michel Jonasz, Jean-Pierre Danel, Eddy Mitchell, Khaled, Natalie Dessay, and Marthe Mercadier.
However, it is Jacques Tati for whom Saint-Mauriens hold the strongest affection. The quirky moviemaker filmed much of his 1958 "My Uncle" ("Mon Oncle"), in Saint-Maur, using many of the locals as extras. It went on to win the best foreign language film Oscar. In Place de la Pelouse stands a bronze statue of Tati as Monsieur Hulot talking to a boy, in a pose echoing the movie’s poster.
Saint-Maur-des-Fossés is almost entirely surrounded by a loop of the Marne River.