Southern Sudan is semi-autonomous region of Sudan, granted certain freedoms as a result of the Comprehensive Peace Agreement (CPA) signed on 9 January 2005 in Naivasha, temporarily bringing to an end the conflict between the government and the Sudan People's Liberation Army (SPLA). The Southern region has a population of around 9 million and a predominantly rural, subsistence economy. The southern Sudanese practice mainly indigenous traditional beliefs, although Christian missionaries have converted some.

The south also contains many tribal groups and many more languages are used than in the north. The Dinka, whose population is estimated at more than 1 million, is the largest of the many black African tribes of the Sudan. Other Nilotic tribes are the Shilluk and the Nuer. The Azande, and Jo Luo are 'Sudanic' tribes in the west, and the Acholi and Lotuhu live in the extreme south, extending into Uganda.

The relationship between autonomous Southern Sudan and the neighbouring areas of Blue Nile State, Nuba Mountains/Southern Kurdufan and Abyei has yet to be definitively determined, although for the time being these are effectively part of the North.

Southern Sudan consists of the ten states, formerly composing the provinces of Equatoria (namely Central Equatoria, East Equatoria, and West Equatoria), Bahr el Ghazal (North Bahr al Ghazal, West Bahr al Ghazal, Lakes, and Warab) and Upper Nile (Junqali, Wahdah, and Upper Nile).

Pending elections, seats in both the Southern Sudan Assembly and the Government of the Southern Sudan are to be divided in a fixed proportion between the SPLM (70%), the NCP (the former NIF) (15%), and other Southern political forces (15%).