It includes the cities of Boucherville, Brossard, Châteauguay, Longueuil, Saint-Hyacinthe, Saint-Jean-sur-Richelieu, Salaberry-de-Valleyfield and Vaudreuil-Dorion.

[3] Samuel de Champlain built several forts to protect the colonists against the Iroquois from south of the Great Lakes, and against the English, who were colonizing New England to the southeast.

The term for naming the set of hills in the St. Lawrence Plain was originally created in 1903 in English by geologist Frank Dawson Adams to designate a new petrographic province.

Montérégie was populated by the St. Lawrence Iroquoian people when the French began to colonize here in the early 16th century.

Later colonists found their villages abandoned, and the area controlled as hunting grounds by the nations of the Iroquoian Confederacy based south of the Great Lakes.

[citation needed] The Montérégie has three administrative subregions, each consisting of its own regional county municipalities (RCM) or equivalent territories.

Akwesasne was established upriver by Mohawk leaders and their families in the mid-18th century, accompanied by French Jesuit missionaries.