Northwestern Ontario is the region within the Canadian province of Ontario which lies north and west of Lake Superior, and west of Hudson Bay and James Bay. It includes most of subarctic Ontario. Its western boundary is the Canadian province of Manitoba, which disputed Ontario's claim to the western part of the region. Ontario's right to Northwestern Ontario was determined by the Judicial Committee of the Privy Council in 1884 and confirmed by the Canada (Ontario Boundary) Act, 1889 of the Parliament of the United Kingdom.
It is the province's most sparsely populated region. Its only major city is Thunder Bay. Smaller communities in the region include Kenora, Dryden, Rainy River, Atikokan, Fort Frances, Sioux Lookout and Central Patricia.
Northwestern Ontario consists of Kenora District, Rainy River District and Thunder Bay District.
Ontario is bounded on the north by Hudson Bay and James Bay, on the east by Quebec, on the west by Manitoba, and on the south by the American states of Minnesota, Wisconsin, Michigan, Ohio, Pennsylvania and New York.
In 1849 the districts of southern Ontario were abolished by the Province of Canada and county governments took over certain municipal responsibilities.
Ontario's right to NorthwesternOntario was determined by the Judicial Committee of the Privy Council in 1884 and confirmed by the Canada (Ontario Boundary) Act, 1889 of the Parliament of the United Kingdom.