Nitassinan is the ancestral homeland of the Algonkian-speaking Innu people, and is closely linked to Innu identity. Nitassinan is home to 10000 Innu, many of whom live in communities at Sheshatshiu on Labrador's Lake Melville, and Utshimassit at Labrador's Davis Inlet.

Geographically defined as a territory consisting of a large part of the subarctic forest, and the barren, interior lands of the Québec-Labrador peninsula in Eastern Québec, Nitassinan serves as a conceptual marker for the space used in the life-sustaining activities of hunting, fishing, and trapping. It is important to note that Nitassinan is both a material region and a spatial concept in which the principles of Innu culture are manifest; a landscape simultaneously cultural and physical.

The climate of Nitassinan is harsh, with a short, cool growing season. Also, there is only one large section of closed canopy forest within the territory. This forest, which provides the needs of human and animal habitat, shelter, as well as Innu wood consumption, has been marked for commercial logging by the provincial government of Newfoundland and Labrador. However, none of the Nitassinan territory has been treatied to the Canadian government. Until the 1960s, the Innu of Nitassinan were primarily nomadic hunters, a task facilitated by the waterways being frozen most of the year. Since then, through the efforts of the Canadian government, and the Catholic church, the Nitassinan have been made to settle in fixed locations.

Of further concern to the Innu people is the use of Nitassinan as a low-level flight-testing ground by NATO aircraft; presently 7000 flights occur over Nitassinan annually, but the provincial and federal governments are lobbying to make Goose Bay, in Labrador, a new flight-training centre, increasing the annual number of flights to 40000.

Archaeologists refer to the original (c. 7000 BCE) First Nations people of the Nitassinan as "Maritime Archaic Indians", and the people of the later wave of First Nation immigration (c. 400 CE) as "Point Revenge Indians". The most recent inhabitants, the Innu, were once referred to as the "Montagnais-Naskapi Indians".