CastorisCausa

Updated: The content of this post was featured in MTL Blog, and prompted an exciting discussion on r/montreal. Lastly, check this awesome video to know more on why it's important to know the terms that Montreal can make reference, as they can be used to mislead in important socioeconomic issues.

P1: I live in Montreal
P2: What does that mean?
P1: That's a very interesting question!

In this time age of wisdom and foolishness, the term Montreal (Montréal in French) can be a little confusing, as it can be used to make reference to many different things, such as:

City of Montreal (Ville de Montréal),
Island of Montreal (Île de Montréal),
Urban agglomeration of Montreal (Agglomération de Montréal),
Greater Montreal (Grand Montréal),
Montreal census metropolitan area (Région métropolitaine de recensement de Montréal), and
Montreal metropolitan community (Communauté métropolitaine de Montréal)

As you may have guessed, all of these terms are not like the others. They are deeply interwoven, and there is overlapping among them. Below their brief definitions, followed by a diagram and map to illustrate their relationship.

The first use of the word Montreal would be the municipality of the City of Montréal incorporated in 1832. The city responsibilities are related to development and urban planning, housing, roads, community and cultural development, recreation, public transit in urban areas, wastewater treatment, etc. In Quebec the functioning, activities and responsibilities of a city are defined in the Loi sur les cités et villes. The city of Montreal is further divided into 19 boroughs (arrondissements), sadly, none of them is named Montreal, although one is called Montréal-Nord.
Note: Post addresses indicate Montreal as city, and not the borough.
The island of Montreal, well it's an island, it's located in the Saint Lawrence river (Fleuve Saint-Laurent) at the point where the Ottawa river (Rivière des Outaouais) joins. Parts of the city of Montreal and other municipalities are contained in the island. However, not all the territory of the city of Montreal is in the island of Montreal, as there are smaller islands that make part of the city.
Note: The island of Montreal is the most populated island in Canada.
The term Urban agglomeration of Montreal makes reference to one of the 17 Quebec administrative regions. Its territory includes all the territory of the cities that are part of the island of Montreal, including also their respective smaller islands. The urban agglomeration exists to administrate common services in the municipalities of the urban agglomeration. To do so, an urban agglomeration council is established, and each municipality cedes part of their authority to the benefit of this council.
Note: Dorval island (L'Île-Dorval) is the only municipality that is part of the Urban agglomeration of Montreal, but is not located in the island of Montreal.
The Greater Montreal is the metropolitan or urban area that is connected to the city of Montreal. So far so good, but this is an vague term, that is not backed up by a clear definition. Other two terms that make reference to the metropolitan area of Montreal are the: Montreal Metropolitan Community and the The Montreal Census Metropolitan Area.
The Montreal Metropolitan Community (CMM). is a entity comprised of 82 municipalities, including the city of Montreal and surrounding municipalities. It has as goal to promote the intermunicipal collaboration to improve the development of the region in diverse aspects: economy, society, public transportation, environment, etc.
Finally, the Montreal census metropolitan area (CMA) is a geostatistic entity defined by Statistics Canada, as an "Area consisting of one or more neighboring municipalities situated around a major urban core. [It] must have a total population of at least 100,000 of which 50,000 or more live in the urban core." As the definition is based on population, the extension of the territory changes from census to census. There is a large overlap the MMC and the Montreal CMA, but these terms should not be confused. Table showing the differences. As result of this large overlap, a good-enough definition for the Greater Montreal could come either the union or the intersection of the MMC and the Montreal CMA.