It was based on the town of Brockville, on the north shore of the Saint Lawrence River, in the Thousand Islands region.

[1] The Union Act provided that the town of Brockville would constitute one electoral district in the Legislative Assembly of the new Parliament,[2] but gave the Governor General of the Province of Canada the power to draw the boundaries for the electoral district.

[3] The first Governor General, Lord Sydenham, issued a proclamation shortly after the formation of the Province of Canada in early 1841, establishing the boundaries for the electoral district: Brockville was represented by one member in the Legislative Assembly.

[8] It was succeeded by electoral districts of the same name in the House of Commons of Canada[9] and the Legislative Assembly of Ontario.

[10] This article incorporates text from this source, which is in the public domain: Proclamation, Governor General Lord Sydenham, February 27, 1841.