The Tlingit language ( ; Lingít ) is spoken by the Tlingit people of Southeast Alaska and Western Canada and is a branch of the Na-Dene language family. Extensive effort is being put into revitalization programs in Southeast Alaska to revive and preserve the Tlingit language and culture. Missionaries of the Russian Orthodox Church were the first to develop a written version of Tlingit by using the Cyrillic script to record and translate it when the Russian Empire had contact with Alaska and the coast of North America down to Sonoma County, California. After the Alaska Purchase, English-speaking missionaries from the United States developed a written version of the language with the Latin alphabet. History The history of Tlingit is poorly known, mostly because there is no written record until the first contact with Europeans around the 1790s. Documentation was sparse and irregular until the early 20th century. The language appears to have spread northward from the Ketchikan–Saxman area towards the Chilkat region since certain conservative features are reduced gradually from south to north. The shared features between the Eyak language, found around the Copper River delta, and Tongass Tlingit, near the Portland Canal, are all the more striking for the distances that separate them, both geographic and linguistic. Classification Tlingit is currently classified as a distinct and separate branch of Na-Dene, an indigenous language family of North America. Edward Sapir (1915) argued for its inclusion in the Na-Dené family, a claim that was subsequently debated by Franz Boas (1917), P.E. Goddard (1920), and many other prominent linguists of the time. Studies in the late 20th century by (Heinz-)Jürgen Pinnow (1962, 1968, 1970, int. al.) and Michael E. Krauss (1964, 1965, 1969, int. al.) showed a strong connection to Eyak and hence to the Athabaskan languages. Sapir initially proposed a connection between Tlingit and Haida, but the debate over Na-Dene gradually excluded Haida from the discussion. Haida is now considered an isolate, with some borrowing from its long proximity with Tlingit. In 2004, the Haida linguist John Enrico presented new arguments and reopened the debate. Victor Golla writes in his 2011 California Native Languages, "John Enrico, the contemporary linguist with the deepest knowledge of Haida, continues to believe that a real, if distant, genetic relationship connects Haida to Na-Dene[.]" Geographic distribution The Tlingit language is distributed from near the mouth of the Copper River down the open coast of the