The borders of Ontario, its new name in 1867, were provisionally expanded north and west. When the Province of Canada was formed, its borders were not entirely clear, and Ontario claimed eventually to reach all the way to the Rocky Mountains and Arctic Ocean. With Canada's acquisition of Rupert's Land, Ontario was interested in clearly defining its borders, especially since some of the new areas in which it was interested were rapidly growing. After the federal government asked Ontario to pay for construction in the new disputed area, the province asked for an elaboration on its limits, and its boundary was moved north to the 51st parallel north.