The Adar oilfield, also known as the Adar Yale, Adar Yeil or Adaril field, is an oilfield situated in the Melut Basin in South Sudan estimated to contain about 276 million barrels (43,900,000 m3) of oil. The Chevron Corporation discovered the Adar Yale field in 1981, shortly before the start of the Second Sudanese Civil War (1983–2005). Soon after Chevron had suspended operations in 1984, Sudanese government troops began attacking civilian settlements in the area, burning the houses and driving the people away, and in the late 1990s, Nuer militias from Nasir helped the army in clearing away the people to make way for the roads and infrastructure of the oilfield.
President Omar al-Bashir inaugurated the site in March 1997, and it initially produced just 5,000 barrels (790 m3) a day. Production from this oilfield, which lies close to the borders with Sudan and Ethiopia, has the potential to bring significant economic benefits to the region. However, until recently the focus has been on clearing the population away from the oilfield rather than on a longer term strategy for developing the region.China has provided a large investment in the Adar oilfield and others in South Sudan and Sudan and has made plans to make extensive further investments.
Southern Sudanese voted overwhelmingly in favor of independence from Sudan in January 2011, with 98.83% of voters reportedly preferring to split from the North. On 9 July 2011, South Sudan became an independent state, with Kiir as its first president. Kiir positioned himself as a reformer, using his inaugural address to call for the South Sudanese people "to forgive, though we shall not forget" perceived injustices at the hands of the northern Sudanese over the preceding decades and announce a general amnesty for South Sudanese groups that had warred against the SPLM in the past. A few weeks later, he publicly addressed members of the military and police to warn them that rape, torture, and other human rights violations carried out by armed personnel would be considered criminal acts and prosecuted aggressively by the Ministry of Justice.
Kiir faced the first real crisis in his presidency of the Republic of South Sudan in early August 2011, when clashes over cattle erupted between Lou Nuer and Murle people in Jonglei and Warrap states, leaving over 600 dead. Kiir ordered the army to deploy to the unrest-hit areas to quell the violence, and the South Sudanese government claimed the next day that fighting had ended.