In 1780, the first European settlers arrived here.[4] In 1848, the Parish of Saint-Placide was formed when it was separated from the parish of Saint-Benoît. The new parish name was undoubtedly chosen because Saint Placide, a monk of the sixth century, was a disciple of Saint Benedict. In 1853, its post office opened, and in 1855, the Parish Municipality of Saint-Placide was formed.[5]
A wharf, built in 1867, allowed vessels of the Ottawa River Navigation Company to take delivery of wheat at that time in the region.[5]
In 1950, the Village Municipality of Saint-Placide was formed when it separated from the Parish Municipality, and was surrounded by the latter's territory. On August 3, 1994, these municipalities were rejoined again to form the new Municipality of Saint-Placide.[5]
^"Admission et inscriptionArchived 2015-01-31 at the Wayback Machine." Commission scolaire de la Seigneurie-des-Mille-Iles. Retrieved on December 7, 2014. "La Commission scolaire de la Seigneurie-des-Mille-Iles (CSSMI) offre ses services aux résidents des municipalités de : Blainville, Boisbriand, Bois-des-Filion, Deux-Montagnes, Lorraine, Mirabel (Saint-Augustin, Saint-Benoît, Sainte-Scholastique et secteur du Domaine-Vert), Oka, Pointe-Calumet, Rosemère, Sainte-Anne-des-Plaines, Sainte-Marthe-sur-le-Lac, Sainte-Thérèse, Saint-Eustache, Saint-Joseph-du-Lac, Saint-Placide et Terrebonne Ouest."