The city is located at the entrance of a pass leading to the upper part of the Rhône valley.

As such, it has a strategic importance, and defence work were built from the 15th century to control this access.

[4] Saint-Maurice is first mentioned in 200 as Acaun[ensis] [quadragesimae] Gal[liarum].

In respect to Saint Maurice, the name was changed from Acaunum (French: Agaune) to Saint-Maurice in 1003.

[5] Some traces of a Bronze Age settlement were found at the foot of the rocky spur in town.

According to tradition, Saint Maurice and his southern Egyptian companions of the Theban Legion were martyred in Acaunum during the reign of Maximian (286-310).

In 515, the King of Burgundy Sigismund founded the Abbey, which he endowed with rich land.

In 1034, the entire Chablais region, which included Saint-Maurice, was acquired by the Duchy of Savoy.

In 1246 Amadeus IV, Count of Savoy enfeoffed Saint-Maurice to King Henry III of England in return for a pension along with the castles at Bard, Avigliana and Susa.

Count Amadeus V of Savoy confirmed the city charter in 1317, at which time the town had a population of between 1,400 and 1,800.

In 1475 the Lower Valais was ruled by the Seven Zenden as an associate member (Zugewandter Ort) of the Swiss Confederation.

In the following year, 1476, Bern began construction of a castle in the narrow Rhone valley at Saint-Maurice.

However, in 1693 a devastating fire in the town, destroyed the warehouse of the castle and much of the gunpowder that was stored there.

During the Second World War, the fortifications at Saint-Maurice were one of the three main pillars of the National Redoubt.

Between 1898 and 1940, the power plant Bois Noir, supplied the city of Lausanne with electricity.

[5] The abbey building, its treasure, and the Feengrotte which opened in 1863, attract pilgrims and tourists.

The Saint-Amé clinic was founded in 1901 and was rebuilt in 1996 into the Lower Valais geriatrics center.

[5] In 2008, the eleven-member town council had six members of the CVP, four FDP.The Liberals and one representative of the Alliance de gauche.

The citizen's council is managed by a six-member committee, which oversee extensive property, including the campsite Bois Noir, pastures and forests.

[5] Saint-Maurice has an area, as of 2009[update], of 7 square kilometers (2.7 sq mi).

It consists of the town of Saint-Maurice and the hamlets of Épinassey and Les Cases.

The blazon of the municipal coat of arms is Per pale Azure and Gules, overall a Cross Bottony Argent.

[11] Most of the population (as of 2000[update]) speaks French (3,097 or 86.1%) as their first language, Italian is the second most common (123 or 3.4%) and Albanian is the third (112 or 3.1%).

[11] The historical population is given in the following chart:[5][15] Abbey of St. Maurice, Agaunum, Saint-Maurice Castle with the Cantonal Military Museum, Maison de la Pierre and the Bridge over the Rhône (shared with Bex, Vaud) are listed as Swiss heritage site of national significance.

The entire Saint-Maurice castle and city area are part of the Inventory of Swiss Heritage Sites.

In the tertiary sector; 143 or 12.5% were in wholesale or retail sales or the repair of motor vehicles, 150 or 13.1% were in the movement and storage of goods, 94 or 8.2% were in a hotel or restaurant, 17 or 1.5% were in the information industry, 6 or 0.5% were the insurance or financial industry, 27 or 2.4% were technical professionals or scientists, 252 or 22.0% were in education and 251 or 22.0% were in health care.

[11] From the 2000 census[update], 2,720 or 75.6% were Roman Catholic, while 285 or 7.9% belonged to the Swiss Reformed Church.