- Area: 619,745 sq km / 239,285 sq mi
- Population: 12,230,730
- Infant mortality: 62.8 per 1000 births
- Life expectancy: 57.3 yrs
- Urbanisation: 19.6%
- Literacy: 26.8%
The Nilotic people of South Sudan—the Acholi, Anyuak, Bari, Dinka, Nuer, Shilluk, Kaligi (Arabic Feroghe), and others—first entered South Sudan sometime before the 10th century, coinciding with the fall of medieval nubia.
During the period from the 15th to the 19th centuries, tribal migrations, largely from the area of Bahr el Ghazal, brought the Anyuak, Dinka, Nuer and Shilluk to their modern locations of both Bahr El Ghazal and Upper Nile Regions, while the Acholi and Bari settled in Equatoria.
The Azande, Mundu, Avukaya and Baka, who entered South Sudan in the 16th century, established the region's largest state of Equatoria Region.
In the 18th century, the Avungara sib rose to power over the rest of Azande society and this domination continued into the 20th century.
Geographical barriers, including the swamplands along the White Nile and the British preference for sending Christian missionaries to the southern regions, including its Closed District Ordinance of 1922 helped to prevent the spread of Islam to the southerners, thus enabling them to retain their social and cultural heritage, as well as their political and religious institutions.
The major reasons include the long history of British policy preference toward developing the Arab north and its ignoring the Black south. After Sudan's first independent elections in 1958, the continued ignoring of the south by Khartoum (lack of schools, roads, bridges) led to uprisings, revolt, and the longest civil war on the continent.
Slavery had been an institution of Sudanese life throughout history. The slave trade in the south intensified in the 19th century, and continued after the British had suppressed slavery in much of sub-Saharan Africa. Annual Sudanese slave raids into non-Muslim territories resulted in the capture of countless thousands of southern Sudanese, and the destruction of the region's stability and economy.
In the 19th century, the Azande fought the French, the Belgians and the Mahdists to maintain their independence. Egypt, under the rule of Khedive Ismail Pasha, first attempted to control the region in the 1870s, establishing the province of Equatoria in the southern portion. Egypt's first governor was Samuel Baker, commissioned in 1869, followed by Charles George Gordon in 1874 and by Emin Pasha in 1878.
The Mahdist Revolt of the 1880s destabilized the nascent province, and Equatoria ceased to exist as an Egyptian outpost in 1889.
European colonial maneuverings in the region came to a head in 1898, when the Fashoda Incident occurred at present-day Kodok; Britain and France almost went to war over the region.
In 1947, British hopes to join South Sudan with Uganda as well as, leaving Western Equatoria as part of The Democratic Republic of Congo were dashed by the Rajaf Conference to unify North and South Sudan.
The region has been negatively affected by two civil wars since Sudanese independence: from 1955 to 1972, the Sudanese government fought the Anyanya rebel army during the First Sudanese Civil War, followed by the Sudan People's Liberation Army/Movement (SPLA/M) in the Second Sudanese Civil War for over 20 years. As a result, the country suffered serious neglect, a lack of infrastructural development, and major destruction and displacement. More than 2.5 million people have been killed and millions more have become refugees both within and outside the country.
Between 9 and 15 January 2011, a referendum was held to determine whether South Sudan should become an independent country and separate from Sudan. 98.83% of the population voted for independence. South Sudan formally became independent from Sudan on 9 July.
In March 2012, South Sudanese forces seized the Heglig oil fields in lands claimed by both Sudan and South Sudan in the province of South Kordofan after conflict with Sudanese forces in the South Sudanese state of Unity. South Sudan withdrew on 20 March, and the Sudanese Army entered Heglig two days later.
In December 2013, a political power struggle broke out between President Kiir and his former deputy Riek Machar, as the president accused Machar and ten others of attempting a coup d'état. Fighting broke out, igniting the South Sudanese Civil War. Ugandan troops were deployed to fight alongside South Sudanese government forces against the rebels. The United Nations has peacekeepers in the country as part of the United Nations Mission in South Sudan (UNMISS). Numerous ceasefires were mediated by the Intergovernmental Authority on Development (IGAD) between the Sudan People's Liberation Movement (SPLM) and SPLM – in opposition and were subsequently broken. A peace agreement was signed in Ethiopia under threat of United Nations sanctions for both sides in August 2015.
Boma National Park, west of the Ethiopian border, as well as the Sudd wetland and Southern National Park near the border with Congo, provided habitat for large populations of hartebeest, kob, topi, buffalo, elephants, giraffes, and lions.
South Sudan's forest reserves also provided habitat for bongo, giant forest hogs, red river hogs, forest elephants, chimpanzees, and forest monkeys. Significant, though diminished wildlife populations still exist, and that, astonishingly, the huge migration of 1.3 million antelopes in the southeast is substantially intact.
Habitats in the country include grasslands, high-altitude plateaus and escarpments, wooded and grassy savannahs, floodplains and wetlands. Associated wildlife species include the endemic white-eared kob and Nile Lechwe, as well as elephants, giraffes, common eland, giant eland, oryx, lions, African wild dogs, cape buffalo, and topi (locally called tiang). Little is known about the white-eared kob and tiang, both types of antelope, whose magnificent migrations were legendary before the civil war. The Boma-Jonglei Landscape region encompasses Boma National Park, broad pasturelands and floodplains, Bandingilo National Park, and the Sudd, a vast area of swamp and seasonally flooded grasslands that includes the Zeraf Wildlife Reserve.
South Sudan has a climate similar to an Equatorial or tropical climate, characterised by a rainy season of high humidity and large amounts of rainfall followed by a drier season.
The economy of South Sudan is one of the world's most underdeveloped with South Sudan having little existing infrastructure and the highest maternal mortality and female illiteracy rates in the world as of 2011.
South Sudan exports timber to the international market. The region also contains many natural resources such as petroleum, iron ore, copper, chromium ore, zinc, tungsten, mica, silver, gold, diamonds, hardwoods, limestone and hydropower. The country's economy, as in many other developing countries, is heavily dependent on agriculture.
The oilfields in the south have been significant to the economy since the latter part of the 20th century. South Sudan has the third-largest oil reserves in Sub-Saharan Africa. It is also estimated that South Sudan has around 4 times the oil deposits of Sudan.