The territory of the municipality of Saint-Joseph-du-Lac was part of the Lac des Deux-Montagnes Seigneury for over a hundred years.

This seigneury was granted on October 17, 1717, to the Sulpician Order of the Ecclesiastical Seminary of St. Sulpice in Paris, who already were lords of the Island of Montreal.

[4] In 1856, the post office opened, being identified as Saint-Joseph-du-Lac in order to distinguish it from the many other locations called Saint-Joseph.

This led to new housing developments for Montreal commuters and a noticeable growth in population that had previously been stable for nearly 80 years.

The Commission scolaire de la Seigneurie-des-Mille-Îles (CSSMI) operates Francophone public schools.