Blainville is a suburb of Montreal located on the North Shore in southwestern Quebec, Canada. Blainville forms part of the Thérèse-De Blainville Regional County Municipality within the Laurentides region of Quebec. The town sits at the foot of the Laurentian Mountains and is located northwest of downtown Montreal.
Louis de Buade de Frontenac granted a vast territory that includes present-day Blainville to elite members of society, lords ("seigneurs") or seigneurs, to promote the development of New France in 1683. The Seigneurie des Mille Îles (Lordship of the Thousand Islands) encompassed over along the northern shores of the Mille Îles River.
In 1792, a disagreement between Seigneur Hertel and Seigneuresse Lamarque resulted in a division of the seigneurial territory along what was then-called the Great Line (present-day Boulevard du Curé-Labelle or Quebec Route 117).
Blainville is named for the third lord of the seigneurie, Jean-Baptiste Céloron de Blainville (1660-1756).
On 14 June 1968, the parish of Sainte-Thérèse-de-Blainville was divided, and Blainville formed its own town consisting of mostly heretofore undeveloped land. In 2017, the municipality governed subdivided into eleven districts, maintained an independent police force with a budget in excess of 14 million CAD and more than 110 staff, a fire department with over 70 firefighters, who since 2016 also serve the neighbouring municipality of Rosemère, a library with three branches, an arena with two rinks, and an aquatic recreation centre.
In the 2021 Census of Population conducted by Statistics Canada, Blainville had a population of 59819 living in 22424 of its 22859 total private dwellings, a change of from its 2016 population of 56863. With a land area of , it had a population density of in 2021. Over 8% of residents are under 15, whereas 67% are between 15 and 64 and 15% are over 65.
In 2021, 86.5% of Blainville residents were white/European, 12.3% were visible minorities and 1.2% were Indigenous. The largest visible minority groups were Arab (3.