South Sudan

Peace has been elusive in South Sudan, which, with U.S. support, became the world's newest country in 2011. The civil war that erupted there in 2013 featured widespread sexual violence, mass killings, and other atrocities. It displaced over a third of the population and fueled Africa's largest refugee crisis for a decade. An estimated 400,000 people died as a result of the conflict before the most recent peace deal was signed in 2018. Whether the agreement ended the war is debated. Conflict continues to plague the country, and the situation has been deteriorating since 2025.

South Sudan ranks as one of the world's poorest and most fragile states, and as one of the least free and most corrupt. Led by President Salva Kiir, the country has not held elections since independence. Its security forces have "mutilated, tortured, beat, and harassed political opponents, journalists, and human rights activists," per the State Department, and targeted government critics outside the country. In early 2025, Kiir's regime arrested his main rival and co-signatory on the 2018 peace deal, First Vice President Riek Machar, for allegedly inciting rebellion.

The United States, which facilitated the 2005 peace deal that enabled South Sudan's independence from Sudan, has long been the country's largest aid donor and the penholder on the issue in the UN Security Council. Congressional interest, driven historically by humanitarian and human rights concerns, has shaped U.S. policy toward what is now South Sudan for decades. U.S. officials have pushed for all parties to stop attacks and implement the 2018 peace deal, and they have called for Machar's release and a return to dialogue among the agreement's signatories.

Humanitarian Situation

South Sudan faces a severe humanitarian crisis that has grown over the past decade: 10 million people (over 70% of the population) need aid in 2026, per UN estimates, and 7.8 million face acute food insecurity, with some at risk of famine. Over 2.5 million South Sudanese are internally displaced, and fresh fighting has displaced over 400,000 since the start of 2026. Another 2.4 million are refugees in neighboring countries. Sudan overtook South Sudan as Africa's largest refugee crisis in 2024, and South Sudan has faced an influx of over 1.3 million refugees and returnees from its northern neighbor, straining aid operations. South Sudan ranks among the countries most vulnerable to natural hazards and climate shocks and among the most dangerous for aid workers. Government forces have restricted aid access to rebel-held areas and attacked health facilities, but opposition forces have also exploited assistance.

Competing donor priorities and increasing costs have led to growing humanitarian funding gaps since 2020, forcing aid agencies to reduce assistance amid rising needs. Some reports suggest aid cuts have led to deaths. U.S. aid has routinely comprised over half of all humanitarian funding for South Sudan, but it has declined under the Trump Administration and currently constitutes almost a third.

Figure 1. South Sudan Key Facts

Source: CRS map. Data from CIA, World Bank & IMF databases.

Background and Context

South Sudan's independence followed a vote for secession from Sudan after almost 40 years of rebellion. Decades of war had inhibited the development of human capital, basic infrastructure, and formal institutions, fueling humanitarian needs that persisted after independence, despite rich natural resources, including oil fields that once generated 75% of Sudan's oil production. As former rebels, South Sudan's leaders had little experience governing, and corruption and conflict hindered post-war recovery and development.

The civil war in Sudan that led to South Sudan's secession was often characterized as a north-south struggle, but fighting among southern rebel commanders nearly derailed the south's bid for self-determination. Leaders in the Sudan People's Liberation Movement/Army (SPLM/SPLA) vying for power mobilized their supporters along ethnic lines, and Sudan's government nurtured SPLM divisions by financing breakaway factions (a tactic Kiir has adopted). The rebel factions reconciled in the early 2000s, helping the SPLM form a united front in peace talks with Sudan's government, culminating in the 2005 Comprehensive Peace Agreement (CPA). Under the CPA, Sudan remained unified for a six-year interim period before southerners voted on separation.

After the CPA, the SPLM became the south's ruling party. With the death of longtime SPLM leader John Garang just months after the CPA signing, the south lost its leading advocate for a united Sudan, and in 2011, over 98% of its voters chose secession. The new country was awash in small arms, and grievances fueled local rebellions and intercommunal violence. The SPLA, which became South Sudan's army, responded with violent, ethnically targeted disarmament campaigns. Maneuvering ahead of the first post-independence elections planned for 2015 added to these dynamics. A 2013 cabinet reshuffle, in which Kiir dismissed his vice president, Riek Machar, formalized a major fissure in the SPLM. Tensions rose as Machar and other SPLM leaders accused Kiir of becoming increasingly dictatorial, and erupted in December 2013, as the party convened to choose its presidential candidate for the polls.

Civil War

The political dispute that triggered the 2013 crisis was not based on ethnicity, but it overlapped with ethnic grievances, spurring targeted ethnic killings and clashes in the capital and then beyond. It split the military, largely along ethnic lines. Attacks targeting Machar's Nuer ethnic group (the country's second largest) were followed by revenge attacks on Dinka, Kiir's ethnic group (the largest). Machar and some senior Nuer military leaders subsequently declared a rebellion. The ensuing war pitted government forces and ethnic militia loyal to Kiir against forces aligned with Machar. Uganda provided initial military support to Kiir's regime and reportedly facilitated its arms imports.

As the violence spread, over 200,000 people sought refuge at UN peacekeeping bases, which became Protection of Civilians (POC) sites. Some experts assess that the decision by the UN Mission in South Sudan (UNMISS) to shelter civilians may have saved tens of thousands of lives.

The warring parties—Kiir's SPLM-IG (In Government) and Machar's SPLM-IO (In Opposition)—broke multiple ceasefires before, under threat of sanctions, they signed the 2015 Agreement on the Resolution of the Conflict in the Republic of South Sudan (ARCSS). Both parties delayed its implementation until early 2016, when they formed a unity government, with Machar returning as one of two vice presidents. The detente did not last long: clashes between the parties' forces in Juba reignited the war in mid-2016, and Machar, pursued by Kiir's forces, fled the country.

Seeking to maintain the appearance of a unity government, Kiir replaced Machar with his deputy, who had defected, and Kiir sacked SPLM-IO cabinet members and legislators loyal to Machar, who continued to lead the main SPLM-IO faction from exile. The rebellion spread, with defections on both sides and new groups emerging. The war moved into the southern Equatoria region, spurring another insurgency and a refugee surge, and affecting key trade routes.

The UN Security Council, after years of debate, authorized an arms embargo on South Sudan in 2018. Soon after, Kiir, Machar, and several other political leaders signed a new deal, the Revitalized ARCSS (R-ARCSS). Other groups rejected it, saying the deal failed to address the war's root causes. An expanded government was eventually formed in 2020, with Machar returning as one of five vice presidents.

The R-ARCSS curtailed clashes between SPLM-IG and -IO forces, but it did not bring peace. Kiir cultivated opposition defections and used ethnic militia to wage attacks in states affiliated with the opposition, spurring counterattacks from community defense groups like the Nuer White Army. His unilateral replacement of opposition officials in government and detention of Machar and other IO leaders breached the 2018 power-sharing deal, per monitors. Attacks by SPLM-IG forces and airstrikes, some conducted by Uganda, on Nuer villages since early 2025 have escalated hostilities. A UN inquiry has assessed that the regime is "systematically dismantling" the R-ARCSS. Speculation over who might succeed Kiir, reportedly ailing, is also fueling tensions.

The government, ignoring calls for dialogue, aims to hold the country's first elections, originally expected in 2015, in December 2026. Widespread insecurity and active hostilities, political prosecutions, repression, and logistical hurdles may undermine the credibility of any elections.

Justice and Accountability

In 2015, an African Union (AU) Commission of Inquiry reported grounds to believe that war crimes and crimes against humanity had been committed in the civil war, and it recommended the creation of an AU-backed hybrid court to ensure accountability. The UN Commission on Human Rights in South Sudan has since reported other violations it says may amount to war crimes, crimes against humanity, and ethnic cleansing. The proposed hybrid court has yet to be established, and the UN commission has assessed that "pervasive impunity" is fueling violence and instability.

The Economy: Oil, Gold, and Corruption

South Sudan has Africa's fifth-largest proven oil reserves, and the oil sector, which lacks transparency and is rife with corruption, dominates its economy. Oil accounted for 90% of state revenue and 95% of exports before a pipeline that carries the country's oil through Sudan for export was damaged in 2024, cutting revenue by nearly 70%. The government stopped paying salaries to civil servants and security forces for a year, and while the pipeline has been repaired and production has risen, salaries remain in arrears.

Some experts describe South Sudan as a kleptocracy. Power is centralized around Kiir, and beyond Juba, in the absence of a functioning state, informal checkpoints flourish, taxing trade and aid. The illicit trade of gold and timber is facilitated through neighboring countries, notably Uganda.

U.S. Policy and Foreign Assistance

The civil war, corruption, and human rights abuses have strained bilateral ties. The United States has designated over two dozen people and related companies under a South Sudan sanctions regime or Global Magnitsky sanctions. The first Trump Administration pushed the authorization of the UN arms embargo, put 15 oil operators on the Commerce Department's Entity List, and imposed visa restrictions on those undermining peace. The Biden Administration also imposed sanctions and visa restrictions, including for corruption and transnational repression, and issued a business advisory on risks for U.S. companies. The Trump Administration has restricted travel and immigration from South Sudan and restricted visas for government officials for undermining peace. The Administration's decision to terminate Temporary Protected Status for South Sudanese nationals in late 2025 was delayed by a court order, but a June 2026 Supreme Court ruling enables the termination.

U.S. aid, most of it humanitarian, totaled over $700 million annually from 2014 to 2024, then fell to under $300 million in 2025. South Sudan is subject to some aid restrictions in appropriations provisions and based on its use of child soldiers and limited efforts to eliminate human trafficking. Non-humanitarian aid historically focused on health, peace-building, independent media, and civil society. Many of those programs were cut in the Trump Administration's foreign aid review. The Administration has committed $146 million to prevent the spread of infectious diseases in the country under a new three-year health cooperation Memorandum of Understanding. The Administration has provided $100 million to date in FY2026 humanitarian aid via a UN pooled fund and additional funding for Ebola preparedness (due to an outbreak in neighboring countries).