[7] The 19th century also saw the diversification of the seigneury's agricultural activities through increased animal husbandry, orchards, and maple syrup collection.

In 1842, a petition totaling about sixty signatures was presented to Mgr Ignace Bourget, Bishop of Montreal who agreed to the demand, and in the same year he signed a canonical decree officiating the creation of the parish of Saint-Bruno.

In line with the Durham Report's recommendation to modernize municipal structures in 1840 (culminating in the abolition of the seigneury system in 1854) and the Acte pour abroger certaines ordonnances et pour faire de meilleures dispositions pour l'établissement d'autorités locales et municipales dans le Bas-Canada (Act to abrogate certain ordinances and to make better dispositions to establish local and municipal authorities in Lower-Canada), on 1 July 1845 the Legislative Assembly created more than 325 municipal corporations in eastern Canada of which Saint-Bruno, then with a population of 800, was a part.

[citation needed] In 2000, the Parti Québécois governments of Lucien Bouchard and Bernard Landry introduced a series of legislative measures with the intent of reorganizing and merging many of Quebec's municipalities.

In 2002, following the adoption of bill 170, Saint-Bruno merged with other municipalities on Montreal's south shore to form the city of Longueuil.

Saint-Bruno-de-Montarville is served by the Saint-Bruno commuter rail station on the Réseau de transport métropolitain's Mont-Saint-Hilaire line.

The South Shore Protestant Regional School Board previously served the municipality.