Rupert’s Land

Rupert's Land, or Prince Rupert's Land, was a territory in British North America consisting of the Hudson Bay drainage basin, a territory in which a commercial monopoly was operated by the Hudson's Bay Company for 200 years from 1670 to 1870, although numerous aboriginal groups lived in the same territory and disputed the sovereignty of the area. The area once known as Rupert's Land is now mainly a part of Canada, but a small portion is now in the United States of America. It was named after Prince Rupert of the Rhine, a nephew of Charles I and the first Governor of the Hudson's Bay Company. In December 1821 the HBC monopoly was extended from Rupert's Land to the Pacific coast.

Areas belonging to Rupert's Land were mostly in present-day Canada and included the whole of Manitoba, most of Saskatchewan, southern Alberta, southern Nunavut, and northern parts of Ontario and Quebec. It also included present-day United States territory, including parts of the states of Minnesota and North Dakota and very small parts of Montana and South Dakota. The southern border west of Lake of the Woods to the Rocky Mountains was the drainage divide between the Mississippi and Saskatchewan watersheds until the London Convention of 1818 substituted the 49th Parallel.

...
Wikipedia