Inuktitut is an official language in Nunavut. There are, I think, seven official languages in the Northwest Territories, but only English and French in Yukon; although there are eight aboriginal language groups, they are quite small.
There are 23,000 to 25,000 Inuktitut speakers, and I think that virtually all of them are in Nunavut. I'm not aware of a concentration of Inuktitut speakers, possibly in Nunavik in northern--