It was created in 1841, by the merger of two previous electoral districts of the Legislative Assembly of Lower Canada, Dorchester and Beauce.

[3] Under the previous legislation, enacted in 1829, the former district of Dorchester had been based on the seigniory of Lauzon, on the south shore of the Saint Lawrence, near Lévis.

The Dorchester electoral district was thus south of Quebec City, between the Saint Lawrence and the border with the United States, in the current Chaudière-Appalaches administrative region.

[8][9][10] The Dorchester riding was abolished on July 1, 1867, when the British North America Act, 1867 came into force, splitting the Province of Canada into Quebec and Ontario.

[13] 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