Wıı̀lıı̀deh Yatıı̀ is the distinctive dialect of the Tłı̨chǫ (Dogrib) language spoken in and around Dettah, Ndılǫ, and Yellowknife, Northwest Territories, by people of the Yellowknives Dene First Nation, who are also known as Wıı̀lıı̀deh Yellowknives Dene. It is one of two traditional languages of the Wıı̀lıı̀deh Yellowknives Dene, the other being Tetsǫ́t’ıné Yatıé, or Yellowknife, otherwise known as “Chipewyan”. Wıı̀lıı̀deh Yatıı̀ is spoken fluently by most band members over the age of 40, and all Yellowknives Dene elders.
Wıı̀lıı̀deh Yatıı̀ is mutually intelligible with Tłı̨chǫ Yatıı̀, an official language of the Northwest Territories, which means that, from a linguistic point of view, they are not separate languages, but rather two dialects of the same language. However, Wıı̀lıı̀deh Yellowknives Dene have a distinct culture, oral history, and ethnic identity which is different from the Tłı̨chǫ Dene, and in many ways more similar to neighboring Tetsǫ́t’ıné and Dëne Sųłıné peoples. Since Wıı̀lıı̀deh Yellowknives Dene do not feel that their oral history is Tłı̨chǫ history, or that their language is the same as the Tłı̨chǫ language, it is important to respect their wishes that these be passed on separately, and not appropriated by other Dene groups, as part of an indigenous peoples’ right to self-determination.
The majority of the distinctive features of Wıı̀lıı̀deh dialect can be attributed to a Tetsǫ́t’ıné substrate: that is, this dialect is the result, historically, of Tetsǫ́t’ıné speakers learning Tłı̨chǫ, and bringing with them many phonological features, lexical items, and grammatical forms from their ancestral Tetsǫ́t’ıné language. The evidence indicates that this language shift began 150-200 years ago, as a result of the peace treaty between Edzo and Akaitcho, which resulted in a period of intensive contact, friendly relations, and intermarriage between Tetsǫ́t’ıné and Tłı̨chǫ peoples (though it is possible that some bilingualism existed even earlier). Wıı̀lıı̀deh speakers very much wish for their dialect to be preserved and passed on to the next generation through school programs and cultural activities, and also wish to maintain their linguistic and cultural distinctness from the Tłı̨chǫ.
According to Yellowknives Dene elders: most Wıı̀lıı̀deh Yellowknives Dene used to speak Tetsǫ́t’ıné (Yellowknife/Chipewyan) several generations ago; however, Tetsǫ́t’ıné is no longer the first language of the majority of YKDFN band members. Rather, they now speak Wıı̀lıı̀deh. In linguistics, then, we would say that Wıı̀lıı̀deh has a Tetsǫ́t’ıné substrate, or that there is a Tetsǫ́t’ıné substrate in Wıı̀lıı̀deh dialect.