The Northwest Territories is one of three federal territories of Canada. The Northwest Territories entered the Canadian Confederation July 15, 1870, but the current borders were formed April 1, 1999, with the creation of Nunavut.
While neighbouring Nunavut is mostly Arctic tundra, the Northwest Territories has a slightly warmer climate and is mostly boreal forest (taiga), although about half of the territory is north of the tree line.
The name is descriptive, adopted by the British government during the colonial era to indicate where it lay in relation to Rupert’s Land. It is shortened from North-Western Territory (see History). In Inuktitut, the Northwest Territories are referred to as ᓄᓇᑦᓯᐊᖅ (Nunatsiaq), “beautiful land.
Thanks to Wikipedia for the information: http://en.wikipedia.org/wiki/North-West_Territories