The municipality of Saint-Mars-d'Outillé has 2,439 inhabitants and covers an area of 38.04 km². At the confluence between the living areas of Ecommoy and Parigné-l'Évêque, it combines a pleasant natural setting on the edge of the Bercé forest, preserved built heritage and small shops.
- The municipality has:
- School facilities ranging from kindergarten to CM2.
- A multi-sport sports complex, an equestrian centre, a city stadium and a playground.
- Municipal halls to host shows and events all year round.
- A branch of CitéZarts, the community music school.
- A library.
- A municipal lodging for 8 people.
- Thirty associations.
- Local shops.
- Health professionals (doctor, nurses, speech therapists, osteopath, psychologist), a pharmacy.
- A waste collection centre.
Former Gallo-Roman center called "Ostiliacus" (Latin name which means "small iron tool"), the village was then crossed by the 13th and 14th Roman roads. Under Charlemagne, "Oustillé" was a flourishing fortress renowned for the manufacture of its tools and for its fairs. Hélie de La Flèche destroyed the Château de la Fontaine in 1098 to prevent it from falling into the hands of Guillaume le Roux, King of England who burned "Oustillé" in 1099. It was then that the town settled in the current site under the hills of La Roche and Rochefort.
A long English occupation during the 100 years war marked the country: some houses and buildings are still the witnesses of this time.
During the wars of religion, the second castle, Segrais, was destroyed and Jean Dubreuil, Huguenot chief of Le Mans, was massacred there. Calm finally returned between the 16th and 18th centuries. During the revolution, on January 22, 1796, part of the village was burned by the Chouans and 7 inhabitants were massacred.
After the Revolution, the country grew to reach 2500 inhabitants. In 1857 until the 1914-1918 war, it housed a people of farmers, hemp growers, lumberjacks, winegrowers, weavers, spinners and linen merchants, craftsmen and shopkeepers.
