When did Joseph H. Greenberg propose the Nilo-Saharan language family?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Nilo-Saharan languages Distribution of the Nilo-Saharan languages.

The American linguist and anthropologist Joseph H. Greenberg first proposed the Nilo-Saharan language family in his 1963 study, which provided a comprehensive genetic classification of African languages.12

Prior to this, in work published between 1949 and 1954 (reprinted in 1955), Greenberg had postulated a grouping he termed "Chari-Nile," which served as a precursor to the Nilo-Saharan family. In his 1963 follow-up, he expanded this concept by incorporating additional language groups to form the Nilo-Saharan superstock.2