The North-Western Territory was a region of British North America extant until 1870 and named for where it lay in relation to Rupert's Land.

Due to the lack of development, exploration, and cartographic limits of the time, the exact boundaries, ownership, and administration of the region were not precisely defined when the territory was extant.

In accordance with the Royal Proclamation of 1763, large-scale settlement by non-aboriginal people was prohibited until the lands were surrendered by treaty.

The North-Western Territory's boundary with Russian America north of the 60th Parallel had been set at the 141st line of longitude by the Treaty of St. Petersburg in 1825.

In 1868, shortly after Canadian Confederation, the Hudson's Bay Company agreed to surrender its vast territories to the new dominion.