Argenteuil County is an historic county in southwestern Quebec

Quebec

Quebec or is a province in east-central Canada. It is the only Canadian province with a predominantly French-speaking population and the only one whose sole official language is French at the provincial level....

, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

. It was located on the Ottawa River

Ottawa River

The Ottawa River is a river in the Canadian provinces of Ontario and Quebec. For most of its length, it now defines the border between these two provinces.-Geography:...

 between Gatineau

Gatineau

Gatineau is a city in western Quebec, Canada. It is the fourth largest city in the province. It is located on the northern banks of the Ottawa River, immediately across from Ottawa, Ontario, and together they form Canada's National Capital Region. Ottawa and Gatineau comprise a single Census...

 and Montreal

Montreal

Montreal is a city in Canada. It is the largest city in the province of Quebec, the second-largest city in Canada and the seventh largest in North America...

. The county seat was Lachute. Argenteuil was bounded on the north by Terrebonne County, on the east by Deux-Montagnes County, on the west by Papineau County and on the south by the United Counties of Prescott and Russell

Prescott and Russell United Counties, Ontario

The United Counties of Prescott and Russell are consolidated counties located in the Canadian province of Ontario. As of 2006, the population is 80,184. Its county seat is L'Orignal, Ontario. It was created as a result of a merger between Russell County and Prescott County in 1820...

 in Ontario

Ontario

Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

.

In the early 1980s the Quebec's counties were abolished and most of Argenteuil County became the Argenteuil Regional County Municipality

Argenteuil Regional County Municipality, Quebec

Argenteuil Regional County Municipality is located in southern Quebec, Canada, part of the Laurentides region. The Regional County Municipality seat is Lachute.-History:...

. The northwestern corner was transferred to Les Laurentides Regional County Municipality

Les Laurentides Regional County Municipality, Quebec

Les Laurentides is a Regional County Municipality in southwestern Quebec, Canada, in the Laurentides region. The seat is in Saint-Faustin-Lac-Carré and it is named after the Laurentian Mountains...

 the northern parts to Les Pays-d'en-Haut Regional County Municipality

Les Pays-d'en-Haut Regional County Municipality, Quebec

Les Pays-d'En-Haut is a county regional municipality of Quebec in Canada. The population of the MRC according to the 2006 Census is 36,573-Towns:* Estérel* Sainte-Adèle* Sainte-Marguerite-du-Lac-Masson* Saint-Sauveur-Municipalities:* Lac-des-Seize-Îles...

 and some eastern parts to Deux-Montagnes Regional County Municipality

Deux-Montagnes Regional County Municipality, Quebec

Deux-Montagnes is a regional county municipality in southwestern Quebec, Canada. It is located immediately north of Laval on the north shore of the Rivière des Mille-Îles and on the north shore of the Lake of Two Mountains. The Regional County Municipality seat is Deux-Montagnes...

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