Britain played a leading role in the discovery of Canada and the study of its northern regions. The transformation of Canada into an Arctic Power was the result of the desire of Great Britain to unite all of its possessions in North America into a single whole in order to prevent the United States from seizing them. Since these British possessions in 1850s had a different legal status and the vast majority of the territory of present-day Canada belonged not to Britain itself but to its private company (Hudson's Bay Company), a different mechanism was used to include these territories in the dominion. In 1870 The Hudson's Bay Company sold Rupert’s Land and the North-Western Territory to Canada and then in 1880 Britain transferred its Arctic islands to the dominion. Britain refused to indicate accurately the boundaries of the territory transferred.