The Adamawa-Ubangi languages are spoken in Nigeria, Cameroon, Chad, the Central African Republic, Cameroon, Gabon, the Republic of the Congo, the Democratic Republic of the Congo, and Sudan, by a total of about 12 million people. The family was established by Joseph Greenberg in The Languages of Africa under the name Adamawa-Eastern as a primary branch of the Niger-Congo family, and itself divided in two branches, Adamawa (e.g. Niellim) and Ubangian (e.g. Sango, an Ubangian-based creole). Their closest affiliation is widely believed to be with the Gur languages, and the unity of the Adamawa branch is also frequently questioned. The linguist Roger Blench replaced Adamawa-Ubangi with a Savannas family, which includes Gur, Ubangian, and the various branches of Adamawa as primary nodes.
The Adamawa languages are among the least studied in Africa, and include many endangered languages; by far the largest of the nearly one hundred small Adamawa languages is Mumuye, at 400,000 speakers. A couple of unclassified languages - notably Laal and Jalaa - are found along their fringes. Ubangian languages, while nearly as numerous, are somewhat better studied; one in particular, Sango, has (in creolized form) become a major trade language of central Africa.
Adamawa-Ubangi languages often have partial vowel harmony, involving restrictions on the co-occurrence of vowels in a word.
As in most branches of the Niger-Congo phylum, noun class systems are widespread. Adamawa-Ubangi languages are notable for having noun class suffixes rather than prefixes. The noun class system is no longer fully productive in all languages.
Some of the subject pronouns (Boyd 1989) seem to have originally been along the lines of:
The third person pronouns vary widely.
In possessive constructions, the possessed typically precedes the possessor, and sentence order is usually Subject Verb Object.