Languages in the family are indigenous to parts of what are now the United States (Alaska); Canada (Inuit Nunangat) including Nunavut, Northwest Territories (principally in the Inuvialuit Settlement Region), northern Quebec (Nunavik), and northern Labrador (Nunatsiavut); Greenland; and the Russian Far East (Chukchi Peninsula).

Neighbouring varieties are quite similar, although those at the farthest distances from the centre in the Diomede Islands and East Greenland are quite divergent.

[3][6][7] The Eskimoan language family split into the Yupik and Inuit branches around 1,000 years ago.

Alexander Vovin (2015)[9] notes that northern Tungusic languages, which are spoken in eastern Siberia and northeastern China, have Eskaleut loanwords that are not found in Southern Tungusic, implying that Eskaleut was once much more widely spoken in eastern Siberia.

Aleut Sirenik † Alutiiq Central Alaskan Yupʼik Naukan Central Siberian Yupik Iñupiaq Inuvialuktun Inuktitut Greenlandic Eskaleut does not have any genetic relationship to any of the world's other language families, this being generally accepted by linguists at the present time.

The more credible proposals on the external relations of Eskaleut all concern one or more of the language families of northern Eurasia, such as Chukotko-Kamchatkan just across the Bering Strait.

One of the first such proposals, the Eskimo–Uralic hypothesis, was suggested by the pioneering Danish linguist Rasmus Rask in 1818, upon noticing similarities between Greenlandic and Finnish.

More recently Joseph Greenberg (2000–2002) suggested grouping Eskaleut with all of the language families of northern Eurasia (Indo-European, Uralic, Altaic, Korean, Japanese, Ainu, Nivkh/Gilayak, and Chukchi–Kamchatkan), with the exception of Yeniseian, in a proposed language family called Eurasiatic.

Criticisms have been made stating that Greenberg's hypothesis is ahistorical, meaning that it lacks and sacrifices known historical elements of language in favour of external similarities.

Greenberg explicitly states that his developments were based on the previous macro-comparative work done by Vladislav Illich-Svitych and Bomhard and Kerns.

Despite all these efforts, the Eurasiatic language theory was overruled on the basis that mass comparison is not accurate enough an approach.

[12] Eskaleut languages have a relatively small number of roots: in the case of Central Alaskan Yup'ik, around two thousand.

If the meaning of the postbase is to be expressed alone, a special neutral root (in the case of Central Alaskan Yup'ik and Inuktitut pi) is used.

The root (or free morpheme) 'angyagh' and the inflection '-tuq' on the right consist of the indicative mood marker plus third person singular.

[14] Following the postbases are non-lexical suffixes that indicate case on nouns and person and mood on verbs.

At the end of a word there can be one of a small number of clitics with meanings such as "but" or indicating a polar question.

Eskaleut is polysynthetic, which features a process in which a single word is able to contain multiple post-bases or morphemes.

The Eskaleut languages are exclusively suffixing (with the exception of one prefix in Inuktitut that appears in demonstratives).

For example, in Central Alaskan Yupik, one can say: qayar-kayak-pa-big-li-make-qa-POL-EV-sqe-A.ask-ssaage-but-llru-PAST-aqa1SG/3SG.INDqayar- pa- li- qa- sqe- ssaage- llru- aqakayak- big- make- POL-EV- A.ask- but- PAST- 1SG/3SG.INDI asked him to make a big kayak.

The two language branches, although part of the same family, have separated and detached themselves in relation to grammatical similarities.

The case inflections, "relative *-m, instrumental *-mEk/meN, and locative *-mi[19] have undergone phonological merger and led to a completely different explanation of ergative morphology in Proto-Eskimoan.