It was created in the British North America Act, 1867.

This riding was set by the British North America Act, 1867 to consist of Antigonish County.

The county was legally defined in 1828 (as Sydney County) as: Commencing at a slate rock, on the Eastern side of the falls of the River Ekimsegam, and at a post and pile of stones marked on the west side CH on the Eastern side CS from thence running North twenty five miles and a quarter of a mile to a square post surrounded by a pile of stones marked SC on the east and HC on the west side from thence running south eighty five degrees, east fourteen miles to a square post and pile of stones marked CS on the Eastern side and CH on the western side, thence running north twenty six miles to the shore of the Gulf of St. Lawrence to a square post surrounded by a pile of stones and marked on the east side CS on the west side CH thence easterly along the shore to the entrance of the Gut of Canso, and by a line drawn through the centre of said Gut southerly to the southern entrance of the same, thence westerly and southerly along the shores of Chedabucto Bay, and easterly along the shore of said bay, and westerly by the southern shore of the province, to Ekimsegum aforenamed comprehending all the Islands in front of the foregoing limits save the Island of Cape Breton, and its appendant Isles.

[1] On Mr. McIsaac being appointed Railway Commissioner, 3 July 1905 On Mr. Thompson's death, 12 December 1894 On Mr. McIsaac being appointed County Court Judge for District No.

6, 24 September 1885 On Mr. McDonald being appointed Puisne Judge of the Supreme Court of Nova Scotia, 5 November 1873 On Mr. McDonald being appointed Minister of Militia and Defence, 1 July 1873