The Kordofanian languages are a geographic grouping of half a dozen language families spoken in the Nuba Mountains of Kordofan Province, Sudan. In 1963 Joseph Greenberg added them to the Niger–Congo family, creating his Niger–Kordofanian proposal. The Kordofanian languages have not been shown to be more distantly related than other branches of Niger–Congo, however, nor have they been shown to constitute a valid group. Today the Kadu family is excluded, and the others usually included in Niger–Congo proper.