It was created in 1841, and was based on the previous electoral districts of l'Assomption and La Chesnaye (or Lachenaie) in the Legislative Assembly of Lower Canada.

[1] The Union Act provided that while many of the pre-existing electoral boundaries of Lower Canada and Upper Canada would continue to be used in the new Parliament, some electoral districts would be defined directly by the Union Act itself.

[3] The former districts of Lachenaie and l'Assomption had been defined by the 1829 boundaries as follows: With the merger of those counties, the new district stretched from south-west of Montreal (now Les Moulins Regional County Municipality), north across the Saint Lawrence River to the north-west of Montreal (now the L'Assomption Regional County Municipality).

"Party" was a fluid concept, especially during the early years of the Province of Canada.

[8] This article incorporates text from this source, which is in the public domain: Statutes of Lower Canada, 13th Provincial Parliament, 2nd Session (1829), c. 74