South Sudan became an independent nation on July 9, 2011, following a referendum in which 98.83 percent of voters chose separation from Sudan. This made it the world's youngest country and Africa's 54th sovereign state. The new nation emerged after the longest civil war in African history, the Second Sudanese Civil War, which lasted from 1983 to 2005 and killed an estimated 2 million people. The Comprehensive Peace Agreement signed in 2005 ended that conflict and established a six-year timeline toward the independence vote. South Sudan's formation represented the first internationally recognized border change in Africa since Eritrea's independence in 1993.
The roots of South Sudan's separation lie in the First Sudanese Civil War, also called the Anyanya Rebellion, which ran from 1955 to 1972. Joseph Lagu led the Anyanya movement, which fought for greater autonomy from Khartoum. That war ended with the Addis Ababa Agreement of 1972, which granted the south regional autonomy for eleven years. When the Sudanese government abrogated that agreement in 1983 and imposed Sharia law nationwide, the Second Sudanese Civil War began. John Garang founded the Sudan People's Liberation Movement and its armed wing, the Sudan People's Liberation Army, in 1983. Garang led the SPLM/A until his death in a helicopter crash on July 30, 2005, just three weeks after becoming First Vice President of Sudan under the peace agreement. His death is commemorated annually as Martyrs' Day.
Salva Kiir Mayardit succeeded Garang as leader of the SPLM/A and became South Sudan's first president at independence. Kiir, an ethnic Dinka, had served as Garang's deputy throughout the war. Riek Machar, an ethnic Nuer, held various leadership positions in the movement and became vice president after independence. Rebecca Nyandeng De Mabior, Garang's widow, became a prominent political figure and later served as vice president. The ethnic composition of leadership remained a defining characteristic of South Sudanese politics.
The Dinka are South Sudan's largest ethnic group, concentrated primarily in the Bahr el Ghazal and Upper Nile regions. The Nuer are the second-largest group, also predominantly in Upper Nile. Other major groups include the Shilluk along the White Nile north of Malakal, the Azande in Western Equatoria, the Bari around Juba, the Murle in Jonglei State, and the Toposa in Eastern Equatoria. The Kakwa, Mundari, Lotuko, Acholi, and Anyuak constitute additional significant populations. South Sudan recognizes more than 60 distinct ethnic groups. Most South Sudanese practice Christianity or traditional African religions, a distinction from the predominantly Muslim north that formed part of the rationale for separation.
English serves as the official language of South Sudan, a deliberate choice to differentiate the new nation from Arabic-speaking Sudan. In practice, Juba Arabic functions as the lingua franca for inter-ethnic communication. Juba Arabic developed as a pidgin during the colonial period and differs substantially from Sudanese Arabic or Modern Standard Arabic. Dinka, Nuer, Bari, Zande, and Shilluk are spoken widely within their respective communities. The linguistic diversity reflects the country's ethnic heterogeneity and the absence of a single dominant culture before independence.
Two years after independence, South Sudan descended into its own civil war. On December 15, 2013, fighting broke out in Juba between forces loyal to President Kiir and those supporting Vice President Machar. What began as a political power struggle within the SPLM rapidly assumed an ethnic dimension, with Dinka-majority government forces fighting primarily Nuer opposition groups. The conflict killed an estimated 400,000 people and displaced 4 million, roughly one-third of the population. Multiple peace agreements failed before the Revitalized Agreement on the Resolution of the Conflict in South Sudan, signed in 2018 and implemented in 2020, established a fragile transitional government with Machar returning as first vice president.
The capital Juba, located on the White Nile in Central Equatoria, grew rapidly after becoming the regional capital of southern Sudan in 2005. The city's population expanded from approximately 100,000 in the 1980s to over 500,000 by independence and continues to grow despite inadequate infrastructure. Other major urban centers include Wau in Western Bahr el Ghazal, Malakal in Upper Nile, and Yei in Central Equatoria. Bor in Jonglei State serves as a regional hub for Dinka populations. Rumbek, Yambio, Aweil, Bentiu, and Torit function as state capitals. Urbanization remains limited, with most South Sudanese living in rural areas practicing subsistence agriculture or pastoralism.