After the Deed of Surrender was enacted in 1870, the United Kingdom transferred the North-Western Territory and Rupert's Land to the government of Canada, with most all of the newly transferred territory administered as the "North-West Territory" (later renamed the "Northwest Territory" in 1912). The territory reached its largest size in 1880, after the British Arctic Territories were transferred from the United Kingdom to Canada, and incorporated into the North-West Territory. However, the size of the territory was reduced several times during the late 18th- and early 19th centuries. Major adjustments to the boundary of the territory during this period includes severing of its western portions to form the territory of Yukon in 1898, severing its southwestern portions to form the provinces of Alberta and Saskatchewan in 1905, and transferring its remaining lands south of the 60th parallel north and the District of Ungava to the provinces of Manitoba, Ontario, and Quebec in 1912.