Welcome to our Navajo language page, featuring books, courses, and software for Navajo. Navajo is an Athabaskan language of the Navajo spoken in southwest of the United States. It is one of the few Southern Athabaskan languages (most existing in Canada and Alaska). Navajo is the most spokenNative American language within the United States, with nearly 150,000 native speakers, and this number has been increasing. During World War II, the Navajo language and Navajo speakers were used to build a code that would be unbreakable by the Japanese military, who would not have access to native speakers.