Sudan's ethnic and linguistic diversity remained one of the most complex in the world in 1991. Its nearly 600 ethnic groups spoke more than 400 languages and dialects, many of them intelligible to only a small number of individuals. In the 1980s and 1990s some of these small groups became absorbed by larger groups, while migration often caused individuals reared in one tongue to converse only in the dominant language of the new area. Such was the case with migrants to the Three Towns. There Arabic was the lingua franca despite the use of English by many of the elite. Some linguistic groups had been absorbed by accommodation, others by conflict. Most Sudanese were, of necessity, multilingual. Choice of language played a political role in the ethnic and religious cleavage between the northern and southern Sudanese. English was associated with being non-Muslim, as Arabic was associated with Islam. Thus language was a political instrument and a symbol of identity.

Data as of June 1991