The basic population of Chad derives from indigenous African groups, whose composition has been altered over the course of years through successive invasions from the Arabic north. The present population is a mixture of at least 200 ethnic groups.
The population can be broadly divided between those who follow the Islamic faith and the peoples of the south, by which is meant the five southernmost prefectures. The Arab invaders brought Islam, perhaps as early as the 8th century, and today their descendants form a relatively homogeneous group, localized in the regions of Chari Baguirmi and Ouaddai, but mostly seminomadic. Muslim indigenous groups include Arabs, Toubou, Hadjerai, Fulbe, Kotoko, Kanembou, Baguirmi, Boulala, Zaghawa, and Maba. Some indigenous groups, such as the Salamat and the Taundjor, were largely Arabized by intermarriage over the years. Other Muslim peoples include the Fulani, the great sheep and goatherders of Chad.
Among the non-Muslim indigenous peoples, the most important (and the largest single group in Chad) are the Sara, about 30% of the population. They live in the valleys of the Chari and Logone rivers and are farmers of considerable skill. Others include the Ngambaye, Mbaye, Goulaye, Moundang, Moussei, and Massa.
There are about 150,00 non-indigenous inhabitants, of whom about 1,000 are French.